Contributions to the study of a class of optimal control problems on the matrix lie group SO(3)
- Authors: Rodgerson, Joanne Kelly
- Date: 2009 , 2013-07-12
- Subjects: Matrix groups , Lie groups , Maximum principles (Mathematics) , Elliptic functions , Extremal problems (Mathematics)
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5421 , http://hdl.handle.net/10962/d1007199 , Matrix groups , Lie groups , Maximum principles (Mathematics) , Elliptic functions , Extremal problems (Mathematics)
- Description: The purpose of this thesis is to investigate a class of four left-invariant optimal control problems on the special orthogonal group SO(3). The set of all control-affine left-invariant control systems on SO(3) can, without loss, be reduced to a class of four typical controllable left-invariant control systems on SO(3) . The left-invariant optimal control problem on SO(3) involves finding a trajectory-control pair on SO (3), which minimizes a cost functional, and satisfies the given dynamical constraints and boundary conditions in a fixed time. The problem is lifted to the cotangent bundle T*SO(3) = SO(3) x so (3)* using the optimal Hamiltonian on so(3)*, where the maximum principle yields the optimal control. In a contribution to the study of this class of optimal control problems on SO(3), the extremal equations on so(3)* (ident ified with JR3) are integrated via elliptic functions to obtain explicit expressions for the solution curves in each typical case. The energy-Casimir method is used to give sufficient conditions for non-linear stability of the equilibrium states. , KMBT_363 , Adobe Acrobat 9.54 Paper Capture Plug-in
- Full Text:
- Authors: Rodgerson, Joanne Kelly
- Date: 2009 , 2013-07-12
- Subjects: Matrix groups , Lie groups , Maximum principles (Mathematics) , Elliptic functions , Extremal problems (Mathematics)
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5421 , http://hdl.handle.net/10962/d1007199 , Matrix groups , Lie groups , Maximum principles (Mathematics) , Elliptic functions , Extremal problems (Mathematics)
- Description: The purpose of this thesis is to investigate a class of four left-invariant optimal control problems on the special orthogonal group SO(3). The set of all control-affine left-invariant control systems on SO(3) can, without loss, be reduced to a class of four typical controllable left-invariant control systems on SO(3) . The left-invariant optimal control problem on SO(3) involves finding a trajectory-control pair on SO (3), which minimizes a cost functional, and satisfies the given dynamical constraints and boundary conditions in a fixed time. The problem is lifted to the cotangent bundle T*SO(3) = SO(3) x so (3)* using the optimal Hamiltonian on so(3)*, where the maximum principle yields the optimal control. In a contribution to the study of this class of optimal control problems on SO(3), the extremal equations on so(3)* (ident ified with JR3) are integrated via elliptic functions to obtain explicit expressions for the solution curves in each typical case. The energy-Casimir method is used to give sufficient conditions for non-linear stability of the equilibrium states. , KMBT_363 , Adobe Acrobat 9.54 Paper Capture Plug-in
- Full Text:
Coping with xenophobia : Senegalese migrants in Port Elizabeth
- Authors: Barbali, Silvana Claudia
- Date: 2009
- Subjects: Xenophobia -- South Africa -- Port Elizabeth Migrant labor -- South Africa -- Port Elizabeth Immigrants -- South Africa -- Port Elizabeth Foreign workers -- South Africa -- Port Elizabeth Aliens -- South Africa -- Social conditions Immigrants -- Africa -- Social conditions
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2102 , http://hdl.handle.net/10962/d1002665
- Description: This thesis seeks to investigate Senegalese migrants' experiences of xenophobia in South Africa. It explores prevailing theories used to explain the phenomenon of xenophobia and uses data collected via anthropological fieldwork to support arguments made. It is argued that a culture of migration in Senegal and the significance of migration as a rite of passage in Senegalese masculinity assists migrants to orientate themselves in host countries, and influences the way Senegalese are „received‟ by South Africans. In addition, Senegalese Islam (Sufi Orientation), which organises its members into brotherhoods, assists in the social integration of Senegalese men in Port Elizabeth. The men belong to the Mouride Brotherhood and the thesis shows how membership to the brotherhood provides a strong network of support for migrant men without resulting in the enclaving of the men in the broader social and economic context of Port Elizabeth. This has important implications for the individual and collective migration experience of Senegalese and influences the men's creation of meaning in their experiences as migrants. The thesis makes use of the concept of transnationalism to analyse the complex and multifaceted nature of transnational migration, arguing that migration experiences are influenced by a range of transnational factors and is deeply culturally influenced. The research suggests that migration experts and government departments in South Africa should take these complexities into account when formulating new programmes and policies for migrants.
- Full Text:
- Authors: Barbali, Silvana Claudia
- Date: 2009
- Subjects: Xenophobia -- South Africa -- Port Elizabeth Migrant labor -- South Africa -- Port Elizabeth Immigrants -- South Africa -- Port Elizabeth Foreign workers -- South Africa -- Port Elizabeth Aliens -- South Africa -- Social conditions Immigrants -- Africa -- Social conditions
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2102 , http://hdl.handle.net/10962/d1002665
- Description: This thesis seeks to investigate Senegalese migrants' experiences of xenophobia in South Africa. It explores prevailing theories used to explain the phenomenon of xenophobia and uses data collected via anthropological fieldwork to support arguments made. It is argued that a culture of migration in Senegal and the significance of migration as a rite of passage in Senegalese masculinity assists migrants to orientate themselves in host countries, and influences the way Senegalese are „received‟ by South Africans. In addition, Senegalese Islam (Sufi Orientation), which organises its members into brotherhoods, assists in the social integration of Senegalese men in Port Elizabeth. The men belong to the Mouride Brotherhood and the thesis shows how membership to the brotherhood provides a strong network of support for migrant men without resulting in the enclaving of the men in the broader social and economic context of Port Elizabeth. This has important implications for the individual and collective migration experience of Senegalese and influences the men's creation of meaning in their experiences as migrants. The thesis makes use of the concept of transnationalism to analyse the complex and multifaceted nature of transnational migration, arguing that migration experiences are influenced by a range of transnational factors and is deeply culturally influenced. The research suggests that migration experts and government departments in South Africa should take these complexities into account when formulating new programmes and policies for migrants.
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Correction, addition and deletion : memory and its function in creating "visual narratives" (and identity) in photographic art
- Authors: Geyer, Xanthe Amanda
- Date: 2009
- Subjects: Botha, Lien, 1961- Photography -- Social aspects Memory in art Photography -- Philosophy Identity (Philosophical concept)
- Language: English
- Type: Thesis , Masters , MFA
- Identifier: vital:2402 , http://hdl.handle.net/10962/d1002198
- Description: With this dissertation I propose to investigate critical theories dealing with memory and its role in photography. The function of memory is a well discussed and analysed topic within the ambit of historical research. Drawing from theoretical texts by critical theorists, namely, Roland Barthes, Annette Kuhn and Marianne Hirsch, I will critically address the function of memory in the understanding of photography; particularly how photographs have the ability to construct our identity in terms of history and narrative. I will study the content of memory in relation to visual images, focusing on what is remembered, what is suppressed, and finally, what is transformed when viewing an image. By doing so, I will consider whether or not still photographs have the ability to construct the past in a narrative form that is intrinsic to its medium. This consideration will be undertaken with specific reference to the works of contemporary South African artist Lien Botha. Special attention will be directed to her series of work entitled Amendment (2006), a series which permits me in turn, to deal with issues pertaining to memory and “visual narrative” which I have explored in my own professional art practice namely, Memory Boxes, Back Stories, Faces of You and Me, Memories Re-layered and Ghostly Remnants.
- Full Text:
- Authors: Geyer, Xanthe Amanda
- Date: 2009
- Subjects: Botha, Lien, 1961- Photography -- Social aspects Memory in art Photography -- Philosophy Identity (Philosophical concept)
- Language: English
- Type: Thesis , Masters , MFA
- Identifier: vital:2402 , http://hdl.handle.net/10962/d1002198
- Description: With this dissertation I propose to investigate critical theories dealing with memory and its role in photography. The function of memory is a well discussed and analysed topic within the ambit of historical research. Drawing from theoretical texts by critical theorists, namely, Roland Barthes, Annette Kuhn and Marianne Hirsch, I will critically address the function of memory in the understanding of photography; particularly how photographs have the ability to construct our identity in terms of history and narrative. I will study the content of memory in relation to visual images, focusing on what is remembered, what is suppressed, and finally, what is transformed when viewing an image. By doing so, I will consider whether or not still photographs have the ability to construct the past in a narrative form that is intrinsic to its medium. This consideration will be undertaken with specific reference to the works of contemporary South African artist Lien Botha. Special attention will be directed to her series of work entitled Amendment (2006), a series which permits me in turn, to deal with issues pertaining to memory and “visual narrative” which I have explored in my own professional art practice namely, Memory Boxes, Back Stories, Faces of You and Me, Memories Re-layered and Ghostly Remnants.
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Creating a virtual classroom: evaluating the use of online discussion forums to increase teaching and learning activities
- Authors: Bezuidenhout, L Peta
- Date: 2009
- Subjects: To be catalogued
- Language: English
- Type: Conference paper
- Identifier: vital:6070 , http://hdl.handle.net/10962/d1004635
- Description: In teaching large classes, the educationally beneficial informal interaction between students and between lecturer and students is generally reduced, while effective use of both students’ and lecturer’s time is often a challenge. During student consultations, especially over the already stressful test and examination periods, many of the questions asked by the students are the same or similar. The lecturer needs to respond to each query by providing the same detailed explanation for the problem, resulting in ineffective use of time for the lecturer, while students waste time waiting for an appointment, or more often, simply don’t bother to follow up on any queries they may have. Having a social presence is important for students’ cognitive development, but in a large class posing questions or interrogating issues during a lecture appears to be challenging for many students. It is often not easy for students to initiate discussions or establish relationships with peers or the lecturer due to feelings of vulnerability and due to the size and impersonal atmosphere of the lecture theatre. This paper deals with the introduction of online discussion forums in an introductory accounting course and the benefits and problems experienced by the students, tutors and lecturer as a result thereof. Feedback received from these participants is discussed. The introduction and use of these forums resulted in a virtual classroom being created, where significantly more teaching and learning activities took place, to the benefit of all participants. Participation could have been peripheral -in the form of simply reading discussions; or active – through posting questions, or responding to questions.
- Full Text:
- Authors: Bezuidenhout, L Peta
- Date: 2009
- Subjects: To be catalogued
- Language: English
- Type: Conference paper
- Identifier: vital:6070 , http://hdl.handle.net/10962/d1004635
- Description: In teaching large classes, the educationally beneficial informal interaction between students and between lecturer and students is generally reduced, while effective use of both students’ and lecturer’s time is often a challenge. During student consultations, especially over the already stressful test and examination periods, many of the questions asked by the students are the same or similar. The lecturer needs to respond to each query by providing the same detailed explanation for the problem, resulting in ineffective use of time for the lecturer, while students waste time waiting for an appointment, or more often, simply don’t bother to follow up on any queries they may have. Having a social presence is important for students’ cognitive development, but in a large class posing questions or interrogating issues during a lecture appears to be challenging for many students. It is often not easy for students to initiate discussions or establish relationships with peers or the lecturer due to feelings of vulnerability and due to the size and impersonal atmosphere of the lecture theatre. This paper deals with the introduction of online discussion forums in an introductory accounting course and the benefits and problems experienced by the students, tutors and lecturer as a result thereof. Feedback received from these participants is discussed. The introduction and use of these forums resulted in a virtual classroom being created, where significantly more teaching and learning activities took place, to the benefit of all participants. Participation could have been peripheral -in the form of simply reading discussions; or active – through posting questions, or responding to questions.
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Cretaceous erosion in central South Africa: evidence from upper-crustal xenoliths in kimberlite diatremes
- Hanson, E Kelsey, Moore, John M, Bordy, Emese M, Marsh, Julian S, Howarth, G, Robey, J V A
- Authors: Hanson, E Kelsey , Moore, John M , Bordy, Emese M , Marsh, Julian S , Howarth, G , Robey, J V A
- Date: 2009
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/144978 , vital:38397 , https://doi.org/10.2113/gssajg.112.2.125
- Description: Twelve Group II and fourteen Group I kimberlite diatremes in central South Africa were examined for upper crustal xenoliths in order to estimate the extent of various lithological units of the Karoo Supergroup in the main Karoo basin at times of kimberlite eruption, the Cretaceous erosional history of the area, and the approximate vertical extent of the kimberlite diatremes prior to erosion. Sandstone and amygdaloidal basaltic lava xenoliths from the Karoo Supergroup were specifically selected as their modal mineralogies and geochemical compositions respectively can be attributed to specific stratigraphic positions within the Karoo Supergroup. Results indicated that, at the time of Group II kimberlite eruption (120 Ma), basaltic lavas of the Drakensberg Group covered the entire area, but by the time of Group I kimberlite eruption (85 Ma), they were restricted to the south-eastern half of the study area.
- Full Text:
- Authors: Hanson, E Kelsey , Moore, John M , Bordy, Emese M , Marsh, Julian S , Howarth, G , Robey, J V A
- Date: 2009
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/144978 , vital:38397 , https://doi.org/10.2113/gssajg.112.2.125
- Description: Twelve Group II and fourteen Group I kimberlite diatremes in central South Africa were examined for upper crustal xenoliths in order to estimate the extent of various lithological units of the Karoo Supergroup in the main Karoo basin at times of kimberlite eruption, the Cretaceous erosional history of the area, and the approximate vertical extent of the kimberlite diatremes prior to erosion. Sandstone and amygdaloidal basaltic lava xenoliths from the Karoo Supergroup were specifically selected as their modal mineralogies and geochemical compositions respectively can be attributed to specific stratigraphic positions within the Karoo Supergroup. Results indicated that, at the time of Group II kimberlite eruption (120 Ma), basaltic lavas of the Drakensberg Group covered the entire area, but by the time of Group I kimberlite eruption (85 Ma), they were restricted to the south-eastern half of the study area.
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Critical reflective teaching practice in three mathematics teachers
- Authors: Luwango, Luiya
- Date: 2009
- Subjects: Education (Secondary) -- Namibia Mathematics teachers -- Training of - -Namibia Mathematics -- Study and teaching (Secondary) -- Namibia
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1485 , http://hdl.handle.net/10962/d1003366
- Description: This qualitative study reports on critical reflective teaching by three mathematics teachers and how it shapes their classroom practice. The study was carried out in three secondary schools in Rundu in northern Namibia. The study employed a case study method. The selection of teachers was based on their rich practical professional knowledge and exemplary teaching practices. Data collection and analysis was done through an interpretive approach. Interviews and document analyses were the two research tools used, not only for the collection of data but for triangulation also. Interpretations of the findings were validated through member checking. Critical reflective teaching involves thought and action, and it raises teachers’ consciousness of what they do. Through critical reflective practice, teachers scrutinize their beliefs and knowledge of the subject and their practice. Furthermore critical reflective practice may get teachers into a disposition to find alternatives to improve their teaching. In this study, the findings are that participants reflect extensively on their classroom practice. The teachers pointed out that reflection on practice enables them to analyse and evaluate their teaching in line with effective mathematics teaching. They emphasised that critical reflection leads to the identification of weaknesses in teachers’ classroom practice. This culminates in better planning whereby alternative approaches to teaching are exercised. Because of its potential to improve teaching and enhance professional development it is therefore recommended that mathematics teachers be exposed to skills that enhance critical reflective teaching practice. Teachers need to familiarise themselves with the concept of critical reflective teaching in mathematics to meet the demands of superior quality teaching.
- Full Text:
- Authors: Luwango, Luiya
- Date: 2009
- Subjects: Education (Secondary) -- Namibia Mathematics teachers -- Training of - -Namibia Mathematics -- Study and teaching (Secondary) -- Namibia
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1485 , http://hdl.handle.net/10962/d1003366
- Description: This qualitative study reports on critical reflective teaching by three mathematics teachers and how it shapes their classroom practice. The study was carried out in three secondary schools in Rundu in northern Namibia. The study employed a case study method. The selection of teachers was based on their rich practical professional knowledge and exemplary teaching practices. Data collection and analysis was done through an interpretive approach. Interviews and document analyses were the two research tools used, not only for the collection of data but for triangulation also. Interpretations of the findings were validated through member checking. Critical reflective teaching involves thought and action, and it raises teachers’ consciousness of what they do. Through critical reflective practice, teachers scrutinize their beliefs and knowledge of the subject and their practice. Furthermore critical reflective practice may get teachers into a disposition to find alternatives to improve their teaching. In this study, the findings are that participants reflect extensively on their classroom practice. The teachers pointed out that reflection on practice enables them to analyse and evaluate their teaching in line with effective mathematics teaching. They emphasised that critical reflection leads to the identification of weaknesses in teachers’ classroom practice. This culminates in better planning whereby alternative approaches to teaching are exercised. Because of its potential to improve teaching and enhance professional development it is therefore recommended that mathematics teachers be exposed to skills that enhance critical reflective teaching practice. Teachers need to familiarise themselves with the concept of critical reflective teaching in mathematics to meet the demands of superior quality teaching.
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Cultural historical activity theory, expansive learning and agency in permaculture workplaces
- Authors: Mukute, Mutizwa
- Date: 2009
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/386474 , vital:68145 , xlink:href="https://www.ajol.info/index.php/sajee/article/view/122818"
- Description: This paper reports on how Cultural Historical Activity Theory was used to identify and analyse contradictions; model and implement solutions in the learning and practice of permaculture at one school and its community in Zimbabwe. This is one of three sustainable agriculture workplace learning sites being examined in a wider study on change-oriented learning and sustainability practices (Mukute, 2009). It gives a brief background to permaculture and the School and Colleges Permaculture Programme (SCOPE) in Zimbabwe. The paper focuses on how contradictions were used as sources of learning and development leading to ‘real life expansions’. This demonstrates and reflects on the value of an interventionist research theory and methodology employed in the study to enhance participants’ agency in sustainable agriculture workplaces.
- Full Text:
- Authors: Mukute, Mutizwa
- Date: 2009
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/386474 , vital:68145 , xlink:href="https://www.ajol.info/index.php/sajee/article/view/122818"
- Description: This paper reports on how Cultural Historical Activity Theory was used to identify and analyse contradictions; model and implement solutions in the learning and practice of permaculture at one school and its community in Zimbabwe. This is one of three sustainable agriculture workplace learning sites being examined in a wider study on change-oriented learning and sustainability practices (Mukute, 2009). It gives a brief background to permaculture and the School and Colleges Permaculture Programme (SCOPE) in Zimbabwe. The paper focuses on how contradictions were used as sources of learning and development leading to ‘real life expansions’. This demonstrates and reflects on the value of an interventionist research theory and methodology employed in the study to enhance participants’ agency in sustainable agriculture workplaces.
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Curiosity first, applications later
- Berold, Robert, Limson, Janice L
- Authors: Berold, Robert , Limson, Janice L
- Date: 2009
- Subjects: Nyokong, Tebello
- Language: English
- Type: Article , text
- Identifier: vital:7188 , http://hdl.handle.net/10962/d1006281 , http://www.sajs.co.za/sites/default/files/publications/pdf/1-4-1-PB.pdf , Nyokong, Tebello
- Description: Tebello Nyokong speaks to Robert Berold and Janice Limson about her career as a chemist. Tebello Nyokong, who holds a research chair in medicinal chemistry and nanotechnology at Rhodes University, has become the first South African scientist to win the L’Oreal-UNESCO award for women in science, in the physical sciences. Only one laureate is selected from each of five world regions, and Nyokong is the 2009 laureate for Africa and the Arab states. She and the winners from the other four regions travel to Paris in March to each accept the award and a generous prize of close to R1 million. Nyokong now heads the new Nanotechnology Innovation Centre for medical sensors: the biggest single research investment in the history of Rhodes. Linked to other nanotechnology centres in the country, it is designed to bridge the gap between research and the market.
- Full Text:
- Authors: Berold, Robert , Limson, Janice L
- Date: 2009
- Subjects: Nyokong, Tebello
- Language: English
- Type: Article , text
- Identifier: vital:7188 , http://hdl.handle.net/10962/d1006281 , http://www.sajs.co.za/sites/default/files/publications/pdf/1-4-1-PB.pdf , Nyokong, Tebello
- Description: Tebello Nyokong speaks to Robert Berold and Janice Limson about her career as a chemist. Tebello Nyokong, who holds a research chair in medicinal chemistry and nanotechnology at Rhodes University, has become the first South African scientist to win the L’Oreal-UNESCO award for women in science, in the physical sciences. Only one laureate is selected from each of five world regions, and Nyokong is the 2009 laureate for Africa and the Arab states. She and the winners from the other four regions travel to Paris in March to each accept the award and a generous prize of close to R1 million. Nyokong now heads the new Nanotechnology Innovation Centre for medical sensors: the biggest single research investment in the history of Rhodes. Linked to other nanotechnology centres in the country, it is designed to bridge the gap between research and the market.
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Dancing around the same spot? land reform and Ngos in Zimbabwe: the case of SOS Children’s Villages
- Authors: Helliker, Kirk D
- Date: 2009
- Language: English
- Type: article , text
- Identifier: http://hdl.handle.net/10962/61006 , vital:27910 , http://dx.doi.org/10.4314/asr.v13i2.60408
- Description: This paper discusses the rural-based operations of an international NGO in Mashonaland Central province, Zimbabwe. The aim is to highlight the contingent variation of NGO practices within defined limits. It does this through 'thick description’ of the NGO of focus, the SOS Children’s Village, and compares its 'handling' of the transforming countryside with the response of two other NGOs. It concludes by suggesting some conceptual points in understanding organizational dispositions of NGOs.
- Full Text:
- Authors: Helliker, Kirk D
- Date: 2009
- Language: English
- Type: article , text
- Identifier: http://hdl.handle.net/10962/61006 , vital:27910 , http://dx.doi.org/10.4314/asr.v13i2.60408
- Description: This paper discusses the rural-based operations of an international NGO in Mashonaland Central province, Zimbabwe. The aim is to highlight the contingent variation of NGO practices within defined limits. It does this through 'thick description’ of the NGO of focus, the SOS Children’s Village, and compares its 'handling' of the transforming countryside with the response of two other NGOs. It concludes by suggesting some conceptual points in understanding organizational dispositions of NGOs.
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Danger and disease in sex education : the saturation of ‘adolescence’ with colonialist assumptions
- Authors: Macleod, Catriona I
- Date: 2009
- Language: English
- Type: Article , text
- Identifier: vital:6252 , http://hdl.handle.net/10962/d1007870
- Description: The United Nations Development Programme’s Millennium project argues for the importance of sexual and reproductive health in the achievement of all Millennium Development Goals. Sex education programmes, aimed principally at the youth, are thus emphasised and are in line with the specific Millennium Development Goals of reducing the incidence of HIV and improving maternal health. In this paper I analyse recent South African sex education and Life Orientation (a learning area containing sex education) manuals. Danger and disease feature as guiding metaphors for these manuals, with early reproduction and abortion being depicted as wholly deleterious and non-normative relationships leading to disease. I argue, firstly, that these renditions ignore well-designed comparative research that calls into questions the easy assumption of negative consequences accompanying ‘teenage pregnancy’ and abortion, and, secondly, that the persistence of danger and disease in sex education programmes is premised on a discourse of ‘adolescence’. ‘Adolescence’ as a concept is always already saturated with the colonialist foundation of phylogeny re-capitulating ontogeny. Individual development is interweaved with collective development with the threat of degeneration implied in both. This interweaving allows for the instrumentalist goal of sex education in which social changes are sought through changing individuals’ sexual attitudes and behaviour.
- Full Text:
- Authors: Macleod, Catriona I
- Date: 2009
- Language: English
- Type: Article , text
- Identifier: vital:6252 , http://hdl.handle.net/10962/d1007870
- Description: The United Nations Development Programme’s Millennium project argues for the importance of sexual and reproductive health in the achievement of all Millennium Development Goals. Sex education programmes, aimed principally at the youth, are thus emphasised and are in line with the specific Millennium Development Goals of reducing the incidence of HIV and improving maternal health. In this paper I analyse recent South African sex education and Life Orientation (a learning area containing sex education) manuals. Danger and disease feature as guiding metaphors for these manuals, with early reproduction and abortion being depicted as wholly deleterious and non-normative relationships leading to disease. I argue, firstly, that these renditions ignore well-designed comparative research that calls into questions the easy assumption of negative consequences accompanying ‘teenage pregnancy’ and abortion, and, secondly, that the persistence of danger and disease in sex education programmes is premised on a discourse of ‘adolescence’. ‘Adolescence’ as a concept is always already saturated with the colonialist foundation of phylogeny re-capitulating ontogeny. Individual development is interweaved with collective development with the threat of degeneration implied in both. This interweaving allows for the instrumentalist goal of sex education in which social changes are sought through changing individuals’ sexual attitudes and behaviour.
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Data quality in thermal summation development models for forensically important blowflies
- Richards, Cameron S, Villet, Martin H
- Authors: Richards, Cameron S , Villet, Martin H
- Date: 2009
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/441889 , vital:73932 , https://doi.org/10.1111/j.1365-2915.2009.00819.x
- Description: To highlight some issues regarding data quality that are significant in estimating post‐mortem intervals (PMI) from maggots, the developmental constants of thermal summation models for development of Chrysomya megacephala Fabricius (Diptera: Calliphoridae) were calculated from incidental data gathered from 12 published studies, and from data generated specifically for the purpose in a single experiment. The focused experiment involved measuring the timing of five developmental landmarks at nine constant temperatures with a sampling resolution of 6–12 h, which is characteristic of other published studies. Combining data from different studies produced inconsistent results because of statistical noise introduced by (at least) disparities in temporal precision, descriptive statistics, geographical location and rearing diets. A robust experimental design to estimate a developmental model should involve at least six constant temperatures, starting at about 7°C above the relevant developmental zero (D0) and going almost to the upper critical temperature, and a temporal sampling interval with a relative precision of about 10%, which requires sampling about every 2 h until hatching, about every 3 h until first ecdysis and about every 6 h until second ecdysis.
- Full Text:
- Authors: Richards, Cameron S , Villet, Martin H
- Date: 2009
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/441889 , vital:73932 , https://doi.org/10.1111/j.1365-2915.2009.00819.x
- Description: To highlight some issues regarding data quality that are significant in estimating post‐mortem intervals (PMI) from maggots, the developmental constants of thermal summation models for development of Chrysomya megacephala Fabricius (Diptera: Calliphoridae) were calculated from incidental data gathered from 12 published studies, and from data generated specifically for the purpose in a single experiment. The focused experiment involved measuring the timing of five developmental landmarks at nine constant temperatures with a sampling resolution of 6–12 h, which is characteristic of other published studies. Combining data from different studies produced inconsistent results because of statistical noise introduced by (at least) disparities in temporal precision, descriptive statistics, geographical location and rearing diets. A robust experimental design to estimate a developmental model should involve at least six constant temperatures, starting at about 7°C above the relevant developmental zero (D0) and going almost to the upper critical temperature, and a temporal sampling interval with a relative precision of about 10%, which requires sampling about every 2 h until hatching, about every 3 h until first ecdysis and about every 6 h until second ecdysis.
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De La Rey rides (yet) again : Afrikaner identity politics and nostalgia in post-apartheid South Africa
- Authors: Baines, Gary F
- Date: 2009
- Language: English
- Type: Conference paper
- Identifier: vital:6158 , http://hdl.handle.net/10962/d1007078
- Description: In 2006 a relatively unknown South African artist with the stage name Bok van Blerk released his debut album called “De la Rey”. The album included a music video of the title track that calls upon the legendary Boer War general to save the volk (people) from the wantonly destructive strategies of the British imperial forces: the scorched earth policy and the subsequent internment of women and children in concentration camps. The British justified such extreme – some would say ‘genocidal’ – strategies so as to prevent non-combatants from supporting the irregular Boer soldiers. Although he did not believe that the war could be won on account of the overwhelming odds that the Boer forces faced, De la Rey still fought to the bitter end. Needless to say, he was on the losing side.
- Full Text:
- Authors: Baines, Gary F
- Date: 2009
- Language: English
- Type: Conference paper
- Identifier: vital:6158 , http://hdl.handle.net/10962/d1007078
- Description: In 2006 a relatively unknown South African artist with the stage name Bok van Blerk released his debut album called “De la Rey”. The album included a music video of the title track that calls upon the legendary Boer War general to save the volk (people) from the wantonly destructive strategies of the British imperial forces: the scorched earth policy and the subsequent internment of women and children in concentration camps. The British justified such extreme – some would say ‘genocidal’ – strategies so as to prevent non-combatants from supporting the irregular Boer soldiers. Although he did not believe that the war could be won on account of the overwhelming odds that the Boer forces faced, De la Rey still fought to the bitter end. Needless to say, he was on the losing side.
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Deconstructing language myths: which languages of learning and teaching in South Africa
- Dalvit, Lorenzo, Murray, Sarah, Terzoli, Alfredo
- Authors: Dalvit, Lorenzo , Murray, Sarah , Terzoli, Alfredo
- Date: 2009
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/431260 , vital:72759 , https://d1wqtxts1xzle7.cloudfront.net/91537059/Deconstructing_language_myths_which_languages_of_learning_and_teaching_in_South_Africa.sflb-libre.pdf?1664136385=response-content-disposi-tion=inline%3B+filename%3DDeconstructing_language_myths_which_lang.pdfExpires=1714984902Signature=dj35y~SObsQq0TnqD-oDUj3CX7lgNnKJcMAchC7rarU74xqfrMlVfOwi-MZrNZvWvpxyzquBsmr1veH-ggRVXQP7TX4eKQq3tXV-gJZg3xyo7QJoGwrGPTjC4btF2kNrVJc6TQulzuPFEz47GtjQ6Nint4SmE7A30EMUMd8j25KgCUdtzqwx9kjBs-niKu~z-pk-Xon5YOolMTepbOwNr9wKGj8JafblTdnFs-H8CZ-Et4BD2mYV3GxnR0QLfgawFgDYkOSZnYhkl6wFsXG~Euwlhcvtp0EgUOfP4id~Ov9hhA-rSQxl81X2Dh1BdMuT3GSsK6VNmO7TikSC7NeGlQ__Key-Pair-Id=APKAJLOHF5GGSLRBV4ZA
- Description: In this article we argue for the use of African languages as Languages of Learning and Teaching (LoLT) for native speakers of such language in South Africa. We believe that both public and academic debate is in-fluenced by a set of ‘language myths’: 1) only one language should be used; 2) the earlier one starts using English as LoLT, the better; 3) us-ing English as LoLT improves English proficiency. These myths be seen as a direct manifestation of Western hegemony, and English-functional arguments are often the terms of reference. We will try a dif-ferent approach by highlighting the advantages of using an African lan-guage (ie isiXhosa) as LoLT and, whenever possible, we will try to put English on the ‘defence stand’. The purpose of this paper is not to ad-vocate the substitution of English with an African language. We believe that bilingual education is the appropriate choice for South Africa, but in order to achieve full equality between English and the African lan-guages in education, arguments in support of the latter must be put forward proactively. With our paper, we hope to contribute to this new perspective.
- Full Text:
- Authors: Dalvit, Lorenzo , Murray, Sarah , Terzoli, Alfredo
- Date: 2009
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/431260 , vital:72759 , https://d1wqtxts1xzle7.cloudfront.net/91537059/Deconstructing_language_myths_which_languages_of_learning_and_teaching_in_South_Africa.sflb-libre.pdf?1664136385=response-content-disposi-tion=inline%3B+filename%3DDeconstructing_language_myths_which_lang.pdfExpires=1714984902Signature=dj35y~SObsQq0TnqD-oDUj3CX7lgNnKJcMAchC7rarU74xqfrMlVfOwi-MZrNZvWvpxyzquBsmr1veH-ggRVXQP7TX4eKQq3tXV-gJZg3xyo7QJoGwrGPTjC4btF2kNrVJc6TQulzuPFEz47GtjQ6Nint4SmE7A30EMUMd8j25KgCUdtzqwx9kjBs-niKu~z-pk-Xon5YOolMTepbOwNr9wKGj8JafblTdnFs-H8CZ-Et4BD2mYV3GxnR0QLfgawFgDYkOSZnYhkl6wFsXG~Euwlhcvtp0EgUOfP4id~Ov9hhA-rSQxl81X2Dh1BdMuT3GSsK6VNmO7TikSC7NeGlQ__Key-Pair-Id=APKAJLOHF5GGSLRBV4ZA
- Description: In this article we argue for the use of African languages as Languages of Learning and Teaching (LoLT) for native speakers of such language in South Africa. We believe that both public and academic debate is in-fluenced by a set of ‘language myths’: 1) only one language should be used; 2) the earlier one starts using English as LoLT, the better; 3) us-ing English as LoLT improves English proficiency. These myths be seen as a direct manifestation of Western hegemony, and English-functional arguments are often the terms of reference. We will try a dif-ferent approach by highlighting the advantages of using an African lan-guage (ie isiXhosa) as LoLT and, whenever possible, we will try to put English on the ‘defence stand’. The purpose of this paper is not to ad-vocate the substitution of English with an African language. We believe that bilingual education is the appropriate choice for South Africa, but in order to achieve full equality between English and the African lan-guages in education, arguments in support of the latter must be put forward proactively. With our paper, we hope to contribute to this new perspective.
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Dedication of Jo'burg's new ring
- Authors: Lewis, Colin A
- Date: 2009
- Language: English
- Type: Article
- Identifier: vital:6189 , http://hdl.handle.net/10962/d1012395 , http://www.ringingworld.co.uk
- Description: Five years of planning, fund raising and hard work came to fruition in November 2008 when Africa's newest ring of bells was dedicated, bringing the first part of the Jo'burg Project to a successful conclusion.
- Full Text:
- Authors: Lewis, Colin A
- Date: 2009
- Language: English
- Type: Article
- Identifier: vital:6189 , http://hdl.handle.net/10962/d1012395 , http://www.ringingworld.co.uk
- Description: Five years of planning, fund raising and hard work came to fruition in November 2008 when Africa's newest ring of bells was dedicated, bringing the first part of the Jo'burg Project to a successful conclusion.
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Deployment and Extension of a Converged WiMAX/WiFi Network for Dwesa Community Area South Africa
- Ndlovu, N, Terzoli, Alfredo, Thinyane, Mamello
- Authors: Ndlovu, N , Terzoli, Alfredo , Thinyane, Mamello
- Date: 2009
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/428479 , vital:72514 , https://citeseerx.ist.psu.edu/document?repid=rep1andtype=pdfanddoi=22468be0252776eabb9e015b51e8e5cf2855ca5f
- Description: As demand for new, reliable, flexible and relatively inexpensive internet access in marginalized rural areas in developing countries increases, there is a need to amalgamate broadband technologies such as WiMAX and WiFi so as to extend the coverage area. Consequently, this will en-able provision of high-speed mobile data and telecommunications ser-vices. This paper describes how WiMAX and WiFi can be merged to-gether, with VSAT technology offering backhaul internet connectivity to provide ever present broadband access. We also look at their respective network applications and how there are going to be used to help support ICT4D activities in these marginalized areas.
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- Authors: Ndlovu, N , Terzoli, Alfredo , Thinyane, Mamello
- Date: 2009
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/428479 , vital:72514 , https://citeseerx.ist.psu.edu/document?repid=rep1andtype=pdfanddoi=22468be0252776eabb9e015b51e8e5cf2855ca5f
- Description: As demand for new, reliable, flexible and relatively inexpensive internet access in marginalized rural areas in developing countries increases, there is a need to amalgamate broadband technologies such as WiMAX and WiFi so as to extend the coverage area. Consequently, this will en-able provision of high-speed mobile data and telecommunications ser-vices. This paper describes how WiMAX and WiFi can be merged to-gether, with VSAT technology offering backhaul internet connectivity to provide ever present broadband access. We also look at their respective network applications and how there are going to be used to help support ICT4D activities in these marginalized areas.
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Determinism and reactive attitudes: reflections on our alleged unrenounceable commitments
- Authors: Kelland, Lindsay-Ann
- Date: 2009
- Subjects: Free will and determinism Responsibility
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2713 , http://hdl.handle.net/10962/d1002843
- Description: There seems to exist a tension between our metaphysical and phenomenological commitments in the free will debate. On the one hand, I argue that at the metaphysical level we cannot coherently defend the belief that we are morally responsible in the sense that we deserve to be rewarded and punished for our actions, where desert-entailing moral responsibility is the primary understanding of moral responsibility presupposed in the free will debate. I argue that we are responsible for our actions but only in the weaker sense, termed ‘attributability’ by Gary Watson. On the other hand, we are allegedly unrenounceably committed at the phenomenological level to conceiving of, and treating, ourselves and one another as morally responsible beings in the desert-entailing sense. P. F. Strawson famously defends this claim in his seminal work, ‘Freedom and Resentment’. In my thesis I will set out this tension by exploring both commitments in turn. I then aim to show that the tension can be dissolved by arguing, contra P. F. Strawson, that our phenomenological commitment is not in fact unrenounceable. The dissolution of this tension entails, I argue, that we must examine our conception of self and other. We must explore the implications of adopting a position which denies that we are morally responsible beings for our life-hopes, personal feelings, inter-personal relationships and projects. Most importantly, I argue that we must renounce our current retributive condemnatory practices which are based on the unjustified belief that we are morally responsible beings.
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- Authors: Kelland, Lindsay-Ann
- Date: 2009
- Subjects: Free will and determinism Responsibility
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2713 , http://hdl.handle.net/10962/d1002843
- Description: There seems to exist a tension between our metaphysical and phenomenological commitments in the free will debate. On the one hand, I argue that at the metaphysical level we cannot coherently defend the belief that we are morally responsible in the sense that we deserve to be rewarded and punished for our actions, where desert-entailing moral responsibility is the primary understanding of moral responsibility presupposed in the free will debate. I argue that we are responsible for our actions but only in the weaker sense, termed ‘attributability’ by Gary Watson. On the other hand, we are allegedly unrenounceably committed at the phenomenological level to conceiving of, and treating, ourselves and one another as morally responsible beings in the desert-entailing sense. P. F. Strawson famously defends this claim in his seminal work, ‘Freedom and Resentment’. In my thesis I will set out this tension by exploring both commitments in turn. I then aim to show that the tension can be dissolved by arguing, contra P. F. Strawson, that our phenomenological commitment is not in fact unrenounceable. The dissolution of this tension entails, I argue, that we must examine our conception of self and other. We must explore the implications of adopting a position which denies that we are morally responsible beings for our life-hopes, personal feelings, inter-personal relationships and projects. Most importantly, I argue that we must renounce our current retributive condemnatory practices which are based on the unjustified belief that we are morally responsible beings.
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Developing an ionospheric map for South Africa
- Authors: Okoh, Daniel Izuikeninachi
- Date: 2009
- Subjects: Ionosphere -- South Africa , Shortwave radio , Ionospheric electron density -- South Africa
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5459 , http://hdl.handle.net/10962/d1005244 , Ionosphere -- South Africa , Shortwave radio , Ionospheric electron density -- South Africa
- Description: This thesis describes the development of an ionospheric map for the South African region using the current available resources. The International Reference Ionosphere (IRI) model, the South African Bottomside Ionospheric Model (SABIM), and measurements from ionosondes in the South African Ionosonde Network, were incorporated into the map. An accurate ionospheric map depicting the foF2 and hmF2 parameters as well as electron density profiles at any location within South Africa is a useful tool for, amongst others, High Frequency (HF) communicators and space weather centers. A major product of the work is software, written in MATLAB, which produces spatial and temporal representations of the South African ionosphere. The map was validated and demonstrated for practical application, since a significant aim of the project was to make the map as applicable as possible. It is hoped that the map will find immense application in HF radio communication industries, research industries, aviation industries, and other industries that make use of Earth-Space systems. A potential user of the map is GrinTek Ewation (GEW) who is currently evaluating it for their purposes
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- Authors: Okoh, Daniel Izuikeninachi
- Date: 2009
- Subjects: Ionosphere -- South Africa , Shortwave radio , Ionospheric electron density -- South Africa
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5459 , http://hdl.handle.net/10962/d1005244 , Ionosphere -- South Africa , Shortwave radio , Ionospheric electron density -- South Africa
- Description: This thesis describes the development of an ionospheric map for the South African region using the current available resources. The International Reference Ionosphere (IRI) model, the South African Bottomside Ionospheric Model (SABIM), and measurements from ionosondes in the South African Ionosonde Network, were incorporated into the map. An accurate ionospheric map depicting the foF2 and hmF2 parameters as well as electron density profiles at any location within South Africa is a useful tool for, amongst others, High Frequency (HF) communicators and space weather centers. A major product of the work is software, written in MATLAB, which produces spatial and temporal representations of the South African ionosphere. The map was validated and demonstrated for practical application, since a significant aim of the project was to make the map as applicable as possible. It is hoped that the map will find immense application in HF radio communication industries, research industries, aviation industries, and other industries that make use of Earth-Space systems. A potential user of the map is GrinTek Ewation (GEW) who is currently evaluating it for their purposes
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Development and validation of a stability-indicating method for the quantitation of paclitaxel in pharmaceutical dosage forms
- Mohammadi, Ali, Esimaeili, Farnaz, Dinarvand, Rasoul, Atyabi, Fatemeh, Walker, Roderick B
- Authors: Mohammadi, Ali , Esimaeili, Farnaz , Dinarvand, Rasoul , Atyabi, Fatemeh , Walker, Roderick B
- Date: 2009
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/184278 , vital:44196 , xlink:href="https://doi.org/10.1093/chromsci/47.7.599"
- Description: A simple, rapid stability-indicating isocratic assay has been developed and validated for the determination of Paclitaxel (PTX) in commercial injection formulations. The assay is performed using a Nucleosil RP-18 (5 µm, 250 × 4.0 mm i.d) column protected by a Nucleosil C18 precolumn (5 µm, 4.0 × 4.0 mm i.d.) with a mobile phase of methanol–water (80:20) and UV detection at 230 nm. The method was found to be specific for PTX in the presence of degradation products with an overall analytical run time of ~ 9 min. Accuracy reported as % bias was found to be 0.1–2.5% bias for all samples tested. Intra-assay precision (repeatability) was found to be 0.22–2.65% RSD, while inter-day precision (intermediate precision) was found to be 1.0–3.0% RSD for the samples studied. The calibration curve was found to be linear with the equation y = 29.78x + 7.65, and a linear regression coefficient of 0.9994 over the concentration range 0.05–20 µg/mL. The limits of quantitation and detection were 0.05 and 0.02 µg/mL, respectively. Taxol (30 mg/5 mL), a commercially available dosage form of PTX, was assayed and 100.6–103.6% of the label claim was recovered.
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- Authors: Mohammadi, Ali , Esimaeili, Farnaz , Dinarvand, Rasoul , Atyabi, Fatemeh , Walker, Roderick B
- Date: 2009
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/184278 , vital:44196 , xlink:href="https://doi.org/10.1093/chromsci/47.7.599"
- Description: A simple, rapid stability-indicating isocratic assay has been developed and validated for the determination of Paclitaxel (PTX) in commercial injection formulations. The assay is performed using a Nucleosil RP-18 (5 µm, 250 × 4.0 mm i.d) column protected by a Nucleosil C18 precolumn (5 µm, 4.0 × 4.0 mm i.d.) with a mobile phase of methanol–water (80:20) and UV detection at 230 nm. The method was found to be specific for PTX in the presence of degradation products with an overall analytical run time of ~ 9 min. Accuracy reported as % bias was found to be 0.1–2.5% bias for all samples tested. Intra-assay precision (repeatability) was found to be 0.22–2.65% RSD, while inter-day precision (intermediate precision) was found to be 1.0–3.0% RSD for the samples studied. The calibration curve was found to be linear with the equation y = 29.78x + 7.65, and a linear regression coefficient of 0.9994 over the concentration range 0.05–20 µg/mL. The limits of quantitation and detection were 0.05 and 0.02 µg/mL, respectively. Taxol (30 mg/5 mL), a commercially available dosage form of PTX, was assayed and 100.6–103.6% of the label claim was recovered.
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Development of a neural network based model for predicting the occurrence of spread F within the Brazilian sector
- Authors: Paradza, Masimba Wellington
- Date: 2009
- Subjects: Neural networks (Computer science) , Ionosphere , F region
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5460 , http://hdl.handle.net/10962/d1005245 , Neural networks (Computer science) , Ionosphere , F region
- Description: Spread F is a phenomenon of the ionosphere in which the pulses returned from the ionosphere are of a much greater duration than the transmitted ones. The occurrence of spread F can be predicted using the technique of Neural Networks (NNs). This thesis presents the development and evaluation of NN based models (two single station models and a regional model) for predicting the occurrence of spread F over selected stations within the Brazilian sector. The input space for the NNs included the day number (seasonal variation), hour (diurnal variation), sunspot number (measure of the solar activity), magnetic index (measure of the magnetic activity) and magnetic position (latitude, magnetic declination and inclination). Twelve years of spread F data measured during 1978 to 1989 inclusively at the equatorial site Fortaleza and low latitude site Cachoeira Paulista are used in the development of an input space and NN architecture for the NN models. Spread F data that is believed to be related to plasma bubble developments (range spread F) were used in the development of the models while those associated with narrow spectrum irregularities that occur near the F layer (frequency spread F) were excluded. The results of the models show the dependency of the probability of spread F as a function of local time, season and latitude. The models also illustrate some characteristics of spread F such as the onset and peak occurrence of spread F as a function of distance from the equator. Results from these models are presented in this thesis and compared to measured data and to modelled data obtained with an empirical model developed for the same purpose.
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- Authors: Paradza, Masimba Wellington
- Date: 2009
- Subjects: Neural networks (Computer science) , Ionosphere , F region
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5460 , http://hdl.handle.net/10962/d1005245 , Neural networks (Computer science) , Ionosphere , F region
- Description: Spread F is a phenomenon of the ionosphere in which the pulses returned from the ionosphere are of a much greater duration than the transmitted ones. The occurrence of spread F can be predicted using the technique of Neural Networks (NNs). This thesis presents the development and evaluation of NN based models (two single station models and a regional model) for predicting the occurrence of spread F over selected stations within the Brazilian sector. The input space for the NNs included the day number (seasonal variation), hour (diurnal variation), sunspot number (measure of the solar activity), magnetic index (measure of the magnetic activity) and magnetic position (latitude, magnetic declination and inclination). Twelve years of spread F data measured during 1978 to 1989 inclusively at the equatorial site Fortaleza and low latitude site Cachoeira Paulista are used in the development of an input space and NN architecture for the NN models. Spread F data that is believed to be related to plasma bubble developments (range spread F) were used in the development of the models while those associated with narrow spectrum irregularities that occur near the F layer (frequency spread F) were excluded. The results of the models show the dependency of the probability of spread F as a function of local time, season and latitude. The models also illustrate some characteristics of spread F such as the onset and peak occurrence of spread F as a function of distance from the equator. Results from these models are presented in this thesis and compared to measured data and to modelled data obtained with an empirical model developed for the same purpose.
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Development of Thanatophilus micans (Fabricius 1794)(Coleoptera: Silphidae) at constant temperatures
- Midgley, John M, Villet, Martin H
- Authors: Midgley, John M , Villet, Martin H
- Date: 2009
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/441904 , vital:73933 , https://doi.org/10.1007/s00414-008-0280-0
- Description: Thanatophilus micans is capable of finding corpses at least as quickly as most fly species and, as the most widespread species of the Silphidae in Africa, offers a useful model for estimating post-mortem interval. Larvae were reared at ten constant temperatures from 15°C to 35°C and their length measured at 4, 8, or 12-h intervals depending on their instar. Length generally increased with increased rearing temperature, but decreased at extremely high temperatures. Note was made of the age at which individuals progressed past developmental milestones. Development took longer at lower temperatures. These results are presented as a combined isomegalen and isomorphen diagram. Developmental constants were generated for each milestone using major axis regression. Developmental threshold values did not differ significantly between milestones. Development took longer than in blow flies, but was faster than in Dermestidae. The three models presented here, therefore, cover an important time frame in estimating minimum PMI once fly larvae have matured to the point of leaving a corpse, and, therefore, provide a tool that was not previously available to forensic entomologists.
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Development of Thanatophilus micans (Fabricius 1794)(Coleoptera: Silphidae) at constant temperatures
- Authors: Midgley, John M , Villet, Martin H
- Date: 2009
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/441904 , vital:73933 , https://doi.org/10.1007/s00414-008-0280-0
- Description: Thanatophilus micans is capable of finding corpses at least as quickly as most fly species and, as the most widespread species of the Silphidae in Africa, offers a useful model for estimating post-mortem interval. Larvae were reared at ten constant temperatures from 15°C to 35°C and their length measured at 4, 8, or 12-h intervals depending on their instar. Length generally increased with increased rearing temperature, but decreased at extremely high temperatures. Note was made of the age at which individuals progressed past developmental milestones. Development took longer at lower temperatures. These results are presented as a combined isomegalen and isomorphen diagram. Developmental constants were generated for each milestone using major axis regression. Developmental threshold values did not differ significantly between milestones. Development took longer than in blow flies, but was faster than in Dermestidae. The three models presented here, therefore, cover an important time frame in estimating minimum PMI once fly larvae have matured to the point of leaving a corpse, and, therefore, provide a tool that was not previously available to forensic entomologists.
- Full Text: