Health, human rights, and the conduct of clinical research within oppressed populations
- Authors: Mills, E J , Singh, S
- Date: 2007
- Language: English
- Type: Article
- Identifier: vital:6411 , http://hdl.handle.net/10962/d1006504 , http://dx.doi.org/10.1186/1744-8603-3-10
- Description: Background Clinical trials evaluating interventions for infectious diseases require enrolling participants that are vulnerable to infection. As clinical trials are conducted in increasingly vulnerable populations, issues of protection of these populations become challenging. In settings where populations are forseeably oppressed, the conduct of research requires considerations that go beyond common ethical concerns and into issues of international human rights law. Discussion Using examples of HIV prevention trials in Thailand, hepatitis-E prevention trials in Nepal and malaria therapeutic trials in Burma (Myanmar), we address the inadequacies of current ethical guidelines when conducting research within oppressed populations. We review existing legislature in the United States and United Kingdom that may be used against foreign investigators if trial hardships exist. We conclude by making considerations for research conducted within oppressed populations.
- Full Text:
- Date Issued: 2007
- Authors: Mills, E J , Singh, S
- Date: 2007
- Language: English
- Type: Article
- Identifier: vital:6411 , http://hdl.handle.net/10962/d1006504 , http://dx.doi.org/10.1186/1744-8603-3-10
- Description: Background Clinical trials evaluating interventions for infectious diseases require enrolling participants that are vulnerable to infection. As clinical trials are conducted in increasingly vulnerable populations, issues of protection of these populations become challenging. In settings where populations are forseeably oppressed, the conduct of research requires considerations that go beyond common ethical concerns and into issues of international human rights law. Discussion Using examples of HIV prevention trials in Thailand, hepatitis-E prevention trials in Nepal and malaria therapeutic trials in Burma (Myanmar), we address the inadequacies of current ethical guidelines when conducting research within oppressed populations. We review existing legislature in the United States and United Kingdom that may be used against foreign investigators if trial hardships exist. We conclude by making considerations for research conducted within oppressed populations.
- Full Text:
- Date Issued: 2007
How entrepreneurs deal with ethical challenges : an application of the Business Ethics Synergy Star Technique
- Robinson, David A, Davidsson, Per, Van der Mescht, Hennie, Court, Philip
- Authors: Robinson, David A , Davidsson, Per , Van der Mescht, Hennie , Court, Philip
- Date: 2007
- Language: English
- Type: Article
- Identifier: vital:6079 , http://hdl.handle.net/10962/d1006123
- Description: Entrepreneurs typically live with the ever present threat of business failure arising from limited financial resources and aggressive competition in the marketplace. Under these circumstances, conflicting priorities arise and the entrepreneur is thus faced with certain dilemmas. In seeking to resolve these, entrepreneurs must often rely on their own judgment to determine ‘‘what is right’’. There is thus a need for a technique to assist them decide on a course of action when no precedent or obvious solution exists. This research paper examines how entrepreneurs experience and deal with these dilemmas. The research is based on interviews with seven entrepreneurs in established service-oriented ventures, which gave rise to 26 dilemmas. These dilemmas were analyzed by making use of the Synergy Star technique, which is introduced here as a tool that is useful in defining any dilemma, isolating the ethical component, and resolving the dilemma in a way that is congruent with the entrepreneur’s personal world-view.
- Full Text:
- Date Issued: 2007
- Authors: Robinson, David A , Davidsson, Per , Van der Mescht, Hennie , Court, Philip
- Date: 2007
- Language: English
- Type: Article
- Identifier: vital:6079 , http://hdl.handle.net/10962/d1006123
- Description: Entrepreneurs typically live with the ever present threat of business failure arising from limited financial resources and aggressive competition in the marketplace. Under these circumstances, conflicting priorities arise and the entrepreneur is thus faced with certain dilemmas. In seeking to resolve these, entrepreneurs must often rely on their own judgment to determine ‘‘what is right’’. There is thus a need for a technique to assist them decide on a course of action when no precedent or obvious solution exists. This research paper examines how entrepreneurs experience and deal with these dilemmas. The research is based on interviews with seven entrepreneurs in established service-oriented ventures, which gave rise to 26 dilemmas. These dilemmas were analyzed by making use of the Synergy Star technique, which is introduced here as a tool that is useful in defining any dilemma, isolating the ethical component, and resolving the dilemma in a way that is congruent with the entrepreneur’s personal world-view.
- Full Text:
- Date Issued: 2007
Impact of nutrients and herbivory by Eccritotarsus catarinensis on the biological control of water hyacinth, Eichhornia crassipes
- Coetzee, Julie A, Byrne, Marcus J, Hill, Martin P
- Authors: Coetzee, Julie A , Byrne, Marcus J , Hill, Martin P
- Date: 2007
- Language: English
- Type: Article
- Identifier: vital:6945 , http://hdl.handle.net/10962/d1011973 , https://orcid.org/0000-0003-0579-5298
- Description: Many water hyacinth infestations in South Africa are the symptom of eutrophication, and as a result, biological control of this weed is variable. This study examined the effects of herbivory by the mirid, Eccritotarsus catarinensis, on water hyacinth grown at high, medium and low nitrogen (N) and phosphorus (P) nutrient concentrations. Water nutrient concentration appears to be the overriding factor affecting plant growth parameters of water hyacinth plants—at high nutrient concentrations, leaf and daughter plant production were more than double than at low nutrient concentrations, while stem length was twice as great at high nutrient concentrations compared to low concentrations. Chlorophyll content was also twice as high at high nutrient concentrations than low concentrations. Conversely, flower production at high nutrient concentrations was less than half that at low concentrations. Herbivory by E. catarinensis did not have as great an effect on water hyacinth vigour as nutrient concentration did, although it significantly reduced the production of daughter plants by 23 ± 9%, the length of the second petiole by 13 ± 5%, and chlorophyll content of water hyacinth leaves by 15 ± 6%. In terms of insect numbers, mirids performed better on plants grown under medium nutrient conditions (99 ± 28 S.E.), compared to high nutrient concentrations (52 ± 27 S.E.), and low nutrient concentrations (25 ± 30 S.E.). Thus, these results suggest that the fastest and most significant reduction in water hyacinth proliferation would be reached by lowering the water nutrient concentrations, and herbivory by E. catarinensis alone is not sufficient to reduce all aspects of water hyacinth vigour, especially at very high nutrient concentrations.
- Full Text:
- Date Issued: 2007
- Authors: Coetzee, Julie A , Byrne, Marcus J , Hill, Martin P
- Date: 2007
- Language: English
- Type: Article
- Identifier: vital:6945 , http://hdl.handle.net/10962/d1011973 , https://orcid.org/0000-0003-0579-5298
- Description: Many water hyacinth infestations in South Africa are the symptom of eutrophication, and as a result, biological control of this weed is variable. This study examined the effects of herbivory by the mirid, Eccritotarsus catarinensis, on water hyacinth grown at high, medium and low nitrogen (N) and phosphorus (P) nutrient concentrations. Water nutrient concentration appears to be the overriding factor affecting plant growth parameters of water hyacinth plants—at high nutrient concentrations, leaf and daughter plant production were more than double than at low nutrient concentrations, while stem length was twice as great at high nutrient concentrations compared to low concentrations. Chlorophyll content was also twice as high at high nutrient concentrations than low concentrations. Conversely, flower production at high nutrient concentrations was less than half that at low concentrations. Herbivory by E. catarinensis did not have as great an effect on water hyacinth vigour as nutrient concentration did, although it significantly reduced the production of daughter plants by 23 ± 9%, the length of the second petiole by 13 ± 5%, and chlorophyll content of water hyacinth leaves by 15 ± 6%. In terms of insect numbers, mirids performed better on plants grown under medium nutrient conditions (99 ± 28 S.E.), compared to high nutrient concentrations (52 ± 27 S.E.), and low nutrient concentrations (25 ± 30 S.E.). Thus, these results suggest that the fastest and most significant reduction in water hyacinth proliferation would be reached by lowering the water nutrient concentrations, and herbivory by E. catarinensis alone is not sufficient to reduce all aspects of water hyacinth vigour, especially at very high nutrient concentrations.
- Full Text:
- Date Issued: 2007
John Michael Berning (14.12.1941- 17.12.2006) : obituary
- Authors: Lewis, Colin A
- Date: 2007
- Language: English
- Type: Article
- Identifier: vital:6184 , http://hdl.handle.net/10962/d1012381
- Description: [From Introduction] Mike Berning was born in 1941. He attended the King Edward VII School in Johannesburg before going up to Rhodes University in 1960, where he read Honours in History, graduating in 1963. Having decided on a career in librarianship, Mike proceeded from Rhodes to the University of Cape Town in 1964, initially to read for a Certificate in that subject. In 1968 he was awarded his Diploma in Librarianship from UCT. In the first part of 1965 Mike was employed in the South African Library in Cape Town, but in September of that year he was appointed Librarian of the Cory Library at Rhodes University. From 1978 until 1986 he acted as Deputy to the University Librarian until, in 1988, the post of Deputy University Librarian was created, to which he was appointed. Mike retired in 1999. , Colin Lewis was Professor of Geography at Rhodes University, Grahamstown, South Africa from 1989 until his retirement at the end of 2007. In 1990, with the strong support of the incumbent Vice-Chancellor, Dr Derek Henderson, he instigated the Certificate in Change Ringing (Church Bell Ringing) in the Rhodes University Department of Music and Musicology - the first such course to be offered in Africa. Since that date he has lectured in the basic theory, and taught the practice of change ringing. He is the Ringing Master of the Cathedral of St Michael and St George, Grahamstown, South Africa.
- Full Text:
- Date Issued: 2007
- Authors: Lewis, Colin A
- Date: 2007
- Language: English
- Type: Article
- Identifier: vital:6184 , http://hdl.handle.net/10962/d1012381
- Description: [From Introduction] Mike Berning was born in 1941. He attended the King Edward VII School in Johannesburg before going up to Rhodes University in 1960, where he read Honours in History, graduating in 1963. Having decided on a career in librarianship, Mike proceeded from Rhodes to the University of Cape Town in 1964, initially to read for a Certificate in that subject. In 1968 he was awarded his Diploma in Librarianship from UCT. In the first part of 1965 Mike was employed in the South African Library in Cape Town, but in September of that year he was appointed Librarian of the Cory Library at Rhodes University. From 1978 until 1986 he acted as Deputy to the University Librarian until, in 1988, the post of Deputy University Librarian was created, to which he was appointed. Mike retired in 1999. , Colin Lewis was Professor of Geography at Rhodes University, Grahamstown, South Africa from 1989 until his retirement at the end of 2007. In 1990, with the strong support of the incumbent Vice-Chancellor, Dr Derek Henderson, he instigated the Certificate in Change Ringing (Church Bell Ringing) in the Rhodes University Department of Music and Musicology - the first such course to be offered in Africa. Since that date he has lectured in the basic theory, and taught the practice of change ringing. He is the Ringing Master of the Cathedral of St Michael and St George, Grahamstown, South Africa.
- Full Text:
- Date Issued: 2007
Karyology of three evolutionarily hexaploid southern African species of yellowfish, Labeobarbus Rüppel, 1836 (Cyprinidae)
- Naran, D, Skelton, Paul H, Villet, Martin H
- Authors: Naran, D , Skelton, Paul H , Villet, Martin H
- Date: 2007
- Language: English
- Type: Article
- Identifier: vital:6855 , http://hdl.handle.net/10962/d1011138 , http://dx.doi.org/10.3377/1562-7020(2007)42[254:KOTEHS]2.0.CO;2
- Description: The karyotypes of three species of yellowfish, namely Labeobarbus marequensis (A. Smith, 1841), L. capensis (A. Smith, 1841) and L. polylepis (Boulenger, 1907), were examined by Giemsa staining using an approach improved for the description of high chromosome numbers. In each case, 2n = 150; no heteromorphic chromosomes were detected; chromosomes in all morphological categories ranged smoothly from large to small, with no distinctly large submetacentric pairs; and metacentric chromosomes showed little variation in size. Labeobarbus marequensis had 26 metacentric (m), 44 submetacentric (sm), 42 subtelocentric (st) and 38 acrocentric (a) chromosomes and a fundamental number (FN) of 262; L. capensis had 16 m, 58 sm, 42 st and 34 a chromosomes and FN = 266; and L. polylepis had 18 m, 60 sm, 42 st and 30 a chromosomes and FN = 270. These results, combined with published literature, imply that Labeobarbus Rüppel, 1836 is an evolutionarily hexaploid African lineage and support its removal from synonymy with the evolutionarily tetraploid Asian genus Tor Gray, 1834. A review of fundamental numbers for conspecific Labeobarbus species examined in different studies implicated karyological technique as a confounding factor in assessing details of karyotypes, leading to recommendations for future karyological studies of barbine fishes. Potential synapomorphies are pointed out in karyological characters of species within Labeobarbus.
- Full Text:
- Date Issued: 2007
- Authors: Naran, D , Skelton, Paul H , Villet, Martin H
- Date: 2007
- Language: English
- Type: Article
- Identifier: vital:6855 , http://hdl.handle.net/10962/d1011138 , http://dx.doi.org/10.3377/1562-7020(2007)42[254:KOTEHS]2.0.CO;2
- Description: The karyotypes of three species of yellowfish, namely Labeobarbus marequensis (A. Smith, 1841), L. capensis (A. Smith, 1841) and L. polylepis (Boulenger, 1907), were examined by Giemsa staining using an approach improved for the description of high chromosome numbers. In each case, 2n = 150; no heteromorphic chromosomes were detected; chromosomes in all morphological categories ranged smoothly from large to small, with no distinctly large submetacentric pairs; and metacentric chromosomes showed little variation in size. Labeobarbus marequensis had 26 metacentric (m), 44 submetacentric (sm), 42 subtelocentric (st) and 38 acrocentric (a) chromosomes and a fundamental number (FN) of 262; L. capensis had 16 m, 58 sm, 42 st and 34 a chromosomes and FN = 266; and L. polylepis had 18 m, 60 sm, 42 st and 30 a chromosomes and FN = 270. These results, combined with published literature, imply that Labeobarbus Rüppel, 1836 is an evolutionarily hexaploid African lineage and support its removal from synonymy with the evolutionarily tetraploid Asian genus Tor Gray, 1834. A review of fundamental numbers for conspecific Labeobarbus species examined in different studies implicated karyological technique as a confounding factor in assessing details of karyotypes, leading to recommendations for future karyological studies of barbine fishes. Potential synapomorphies are pointed out in karyological characters of species within Labeobarbus.
- Full Text:
- Date Issued: 2007
Lessons from the dead masters: Wordsworth and Byron in J. M. Coetzee's Disgrace
- Authors: Beard, Margot
- Date: 2007
- Language: English
- Type: Article
- Identifier: vital:6114 , http://hdl.handle.net/10962/d1003827
- Description: As one whose research interests lie in the field of Romanticism, most specifically Wordsworth and Byron, I was obviously intrigued by J. M. Coetzee's use of these poets in Disgrace. Subsequent readings of the work have convinced me that more attention needs to be paid to the deeper implications of their presence in the text. Certainly many scholars have explored the significance of David Lurie's professional interest in the Romantic poets and the novel's imbeddedness in what Jane Taylor has referred to as "the European Enlightenment's legacy of the autonomy of the individual" as well as a specifically "eighteenth century model of philosophical sympathy" (1999, 25). Yet I feel that insufficient attention has been paid to the significance of Romanticism, the Wordsworthian and the Byronic in the novel. Generally, the commentary ranges from seeing Lurie's academic interests as symptomatic of his white colonialist mentality to a more nuanced but insufficiently developed focus on the possibilities lying behind Coetzee's startling juxtaposition of two of the most famed and yet most overtly antagonistic of the Romantic poets. Zoë Wicomb is representative of the first approach. In her estimation, Lurie may be rejected since he "looks to Europe as the centre of reference" and "our feelings and experiences of nature need not be structured by poetic discourses from the metropolis".
- Full Text:
- Date Issued: 2007
- Authors: Beard, Margot
- Date: 2007
- Language: English
- Type: Article
- Identifier: vital:6114 , http://hdl.handle.net/10962/d1003827
- Description: As one whose research interests lie in the field of Romanticism, most specifically Wordsworth and Byron, I was obviously intrigued by J. M. Coetzee's use of these poets in Disgrace. Subsequent readings of the work have convinced me that more attention needs to be paid to the deeper implications of their presence in the text. Certainly many scholars have explored the significance of David Lurie's professional interest in the Romantic poets and the novel's imbeddedness in what Jane Taylor has referred to as "the European Enlightenment's legacy of the autonomy of the individual" as well as a specifically "eighteenth century model of philosophical sympathy" (1999, 25). Yet I feel that insufficient attention has been paid to the significance of Romanticism, the Wordsworthian and the Byronic in the novel. Generally, the commentary ranges from seeing Lurie's academic interests as symptomatic of his white colonialist mentality to a more nuanced but insufficiently developed focus on the possibilities lying behind Coetzee's startling juxtaposition of two of the most famed and yet most overtly antagonistic of the Romantic poets. Zoë Wicomb is representative of the first approach. In her estimation, Lurie may be rejected since he "looks to Europe as the centre of reference" and "our feelings and experiences of nature need not be structured by poetic discourses from the metropolis".
- Full Text:
- Date Issued: 2007
Load carrying : in situ physiological responses of an infantry platoon
- Scott, Patricia A, Ramabhai, L
- Authors: Scott, Patricia A , Ramabhai, L
- Date: 2007
- Language: English
- Type: Article
- Identifier: vital:6753 , http://hdl.handle.net/10962/d1009333
- Description: Morphological diversity is the source of differential stress when heavy work must be done by groups, as in the carrying of military equipment by a platoon. In this study 10 infantrymen each carried 40.5kg at the same pace over a 12km route on one day and 37% of personal body weight on another occasion. Physiological and perceptual responses indicated less stress was experienced when loads were normalised for morphological differences between the troops.
- Full Text:
- Date Issued: 2007
- Authors: Scott, Patricia A , Ramabhai, L
- Date: 2007
- Language: English
- Type: Article
- Identifier: vital:6753 , http://hdl.handle.net/10962/d1009333
- Description: Morphological diversity is the source of differential stress when heavy work must be done by groups, as in the carrying of military equipment by a platoon. In this study 10 infantrymen each carried 40.5kg at the same pace over a 12km route on one day and 37% of personal body weight on another occasion. Physiological and perceptual responses indicated less stress was experienced when loads were normalised for morphological differences between the troops.
- Full Text:
- Date Issued: 2007
Load stress; carrier strain: implications for military and receational backpacking
- Authors: Charteris, J
- Date: 2007
- Language: English
- Type: Article
- Identifier: vital:6754 , http://hdl.handle.net/10962/d1009456
- Description: This paper reviews a growing literature on the stress of backpacking, particularly in military situations. Conceptual issues are raised and the implications for recreational backpackers are addressed. Under moderate to fairly heavy loading the energy cost, per kg total load carried, per hour, relates almost linearly to walking speed. Empirical data from studies in this unit are presented as benchmark indicators for use by recreational backpackers.
- Full Text:
- Date Issued: 2007
- Authors: Charteris, J
- Date: 2007
- Language: English
- Type: Article
- Identifier: vital:6754 , http://hdl.handle.net/10962/d1009456
- Description: This paper reviews a growing literature on the stress of backpacking, particularly in military situations. Conceptual issues are raised and the implications for recreational backpackers are addressed. Under moderate to fairly heavy loading the energy cost, per kg total load carried, per hour, relates almost linearly to walking speed. Empirical data from studies in this unit are presented as benchmark indicators for use by recreational backpackers.
- Full Text:
- Date Issued: 2007
Mapping GPS-derived ionospheric Total Electron Content over Southern Africa during different epochs of solar cycle 23
- Moeketsi, D M, Combrinck, W L, McKinnell, Lee-Anne, Fedrizz, M
- Authors: Moeketsi, D M , Combrinck, W L , McKinnell, Lee-Anne , Fedrizz, M
- Date: 2007
- Language: English
- Type: Article
- Identifier: vital:6802 , http://hdl.handle.net/10962/d1004165
- Description: The Southern African Development Community and the International Global Navigation Satellite Systems Service (GNSS) network of dual frequency Global Positioning System (GPS) receivers provide an opportunity to determine Total Electron Content (TEC) over Southern Africa by taking advantage of the dispersive nature of the ionospheric medium. For this task, the University of New Brunswick (UNB) ionospheric modelling technique which applies a spatial linear approximation of the vertical TEC above each station using stochastic parameters in Kalman filter estimation, primed with data from the Southern Africa GPS network, was used for mapping TEC at South African locations during selected days and hours of different epochs of solar cycle 23. Significant enhancements in the TEC value and features, which could be associated with frequent solar events, are evident around a day of extreme solar maximum. These observations are discussed and further investigated by analyzing the GOES 8 and 10 satellites X-ray flux (0.1–0.8 nm) and SOHO Solar EUV Monitor (26.0–34.0 nm) higher resolution data. Comparison of these physical quantities reveals that for each X-ray flare observed, there is an associated EUV flare event. The latter phenomenon causes photoionisation in the daytime ionosphere which results in significant TEC enhancement. The daytime UNB TEC compared with the International Reference Ionosphere (IRI) 2001 predicted TEC found both models to show a good agreement.
- Full Text:
- Date Issued: 2007
- Authors: Moeketsi, D M , Combrinck, W L , McKinnell, Lee-Anne , Fedrizz, M
- Date: 2007
- Language: English
- Type: Article
- Identifier: vital:6802 , http://hdl.handle.net/10962/d1004165
- Description: The Southern African Development Community and the International Global Navigation Satellite Systems Service (GNSS) network of dual frequency Global Positioning System (GPS) receivers provide an opportunity to determine Total Electron Content (TEC) over Southern Africa by taking advantage of the dispersive nature of the ionospheric medium. For this task, the University of New Brunswick (UNB) ionospheric modelling technique which applies a spatial linear approximation of the vertical TEC above each station using stochastic parameters in Kalman filter estimation, primed with data from the Southern Africa GPS network, was used for mapping TEC at South African locations during selected days and hours of different epochs of solar cycle 23. Significant enhancements in the TEC value and features, which could be associated with frequent solar events, are evident around a day of extreme solar maximum. These observations are discussed and further investigated by analyzing the GOES 8 and 10 satellites X-ray flux (0.1–0.8 nm) and SOHO Solar EUV Monitor (26.0–34.0 nm) higher resolution data. Comparison of these physical quantities reveals that for each X-ray flare observed, there is an associated EUV flare event. The latter phenomenon causes photoionisation in the daytime ionosphere which results in significant TEC enhancement. The daytime UNB TEC compared with the International Reference Ionosphere (IRI) 2001 predicted TEC found both models to show a good agreement.
- Full Text:
- Date Issued: 2007
Metaphor or reality? The man who went into the west: the life of R.S. Thomas / by Byron Rogers: book review
- Authors: Lewis, Colin A
- Date: 2007
- Language: English
- Type: Article
- Identifier: vital:6188 , http://hdl.handle.net/10962/d1012394
- Description: Colin Lewis was Professor of Geography at Rhodes University, Grahamstown, South Africa from 1989 until his retirement at the end of 2007. In 1990, with the strong support of the incumbent Vice-Chancellor, Dr Derek Henderson, he instigated the Certificate in Change Ringing (Church Bell Ringing) in the Rhodes University Department of Music and Musicology - the first such course to be offered in Africa. Since that date he has lectured in the basic theory, and taught the practice of change ringing. He is the Ringing Master of the Cathedral of St Michael and St George, Grahamstown, South Africa.
- Full Text:
- Date Issued: 2007
- Authors: Lewis, Colin A
- Date: 2007
- Language: English
- Type: Article
- Identifier: vital:6188 , http://hdl.handle.net/10962/d1012394
- Description: Colin Lewis was Professor of Geography at Rhodes University, Grahamstown, South Africa from 1989 until his retirement at the end of 2007. In 1990, with the strong support of the incumbent Vice-Chancellor, Dr Derek Henderson, he instigated the Certificate in Change Ringing (Church Bell Ringing) in the Rhodes University Department of Music and Musicology - the first such course to be offered in Africa. Since that date he has lectured in the basic theory, and taught the practice of change ringing. He is the Ringing Master of the Cathedral of St Michael and St George, Grahamstown, South Africa.
- Full Text:
- Date Issued: 2007
Neural network-based prediction techniques for global modeling of M(3000)F2 ionospheric parameter
- Oyeyemi, E O, McKinnell, Lee-Anne, Poole, Allon W V
- Authors: Oyeyemi, E O , McKinnell, Lee-Anne , Poole, Allon W V
- Date: 2007
- Language: English
- Type: text , Article
- Identifier: vital:6803 , http://hdl.handle.net/10962/d1004166
- Description: In recent times neural networks (NNs) have been employed to solve many problems in ionospheric predictions. This paper illustrates a new application of NNs in developing a global model of the ionospheric propagation factor M(3000)F2. NNs were trained with daily hourly values of M(3000)F2 from various ionospheric stations spanning the period 1964–1986 with the following temporal and spatial input parameters: Universal Time, geographic latitude, magnetic inclination, magnetic declination, solar zenith angle, day of the year, A16 index (a 2-day running mean of the 3-h planetary magnetic ap index), R2 index (a 2-month running mean of sunspot number), and the angle of meridian relative to the subsolar point. The performance of the NNs was verified by comparing the predicted values of M(3000)F2 with observed values from a few selected ionospheric stations and the IRI (International Reference Ionosphere) model (CCIR M(3000)F2 model) predicted values. The results obtained compared favourably with the IRI model. Based on the error differences, the result obtained justifies the potential of the NN technique for the predictions of M(3000)F2 values on a global scale.
- Full Text:
- Date Issued: 2007
- Authors: Oyeyemi, E O , McKinnell, Lee-Anne , Poole, Allon W V
- Date: 2007
- Language: English
- Type: text , Article
- Identifier: vital:6803 , http://hdl.handle.net/10962/d1004166
- Description: In recent times neural networks (NNs) have been employed to solve many problems in ionospheric predictions. This paper illustrates a new application of NNs in developing a global model of the ionospheric propagation factor M(3000)F2. NNs were trained with daily hourly values of M(3000)F2 from various ionospheric stations spanning the period 1964–1986 with the following temporal and spatial input parameters: Universal Time, geographic latitude, magnetic inclination, magnetic declination, solar zenith angle, day of the year, A16 index (a 2-day running mean of the 3-h planetary magnetic ap index), R2 index (a 2-month running mean of sunspot number), and the angle of meridian relative to the subsolar point. The performance of the NNs was verified by comparing the predicted values of M(3000)F2 with observed values from a few selected ionospheric stations and the IRI (International Reference Ionosphere) model (CCIR M(3000)F2 model) predicted values. The results obtained compared favourably with the IRI model. Based on the error differences, the result obtained justifies the potential of the NN technique for the predictions of M(3000)F2 values on a global scale.
- Full Text:
- Date Issued: 2007
Olive Schreiner in Rhodesia: an episode in a biography
- Walters, Paul S, Fogg, W Jeremy M
- Authors: Walters, Paul S , Fogg, W Jeremy M
- Date: 2007
- Language: English
- Type: text , Article
- Identifier: vital:6123 , http://hdl.handle.net/10962/d1004707
- Description: Readers of biographies of Olive Schreiner - except for the pioneering work of Vera Buchanan-Gould (see 1948, 198-99) - could be forgiven for doubting whether Olive Schreiner ever was in Rhodesia. Although her husband's edition of her Letters includes three which cover this journey (Cronwright-Schreiner 1924a), he makes no mention of it in his Life (1924), and it is not touched on either in First and Scott (1980) or in Stanley's impressive biographical chapter (2002). Arguably, it does nothing to alter the by now well-established outlines of Olive Schreiner's life; yet, as we shall see, the visit itself might have meant the premature end of that life. Moreover, it documents Schreiner's visit to two sites of immense importance to her : the 'Hanging Tree' in Bulawayo which features in the (deliberately shocking) photographic frontispiece to the first edition of Trooper Peter Halket of Mashonaland (1897), and, secondly, Cecil Rhodes's grave in the Matopos. In just over a decade (13 Aug. 1921), she too would lie in her chosen mountaintop tomb.
- Full Text:
- Date Issued: 2007
- Authors: Walters, Paul S , Fogg, W Jeremy M
- Date: 2007
- Language: English
- Type: text , Article
- Identifier: vital:6123 , http://hdl.handle.net/10962/d1004707
- Description: Readers of biographies of Olive Schreiner - except for the pioneering work of Vera Buchanan-Gould (see 1948, 198-99) - could be forgiven for doubting whether Olive Schreiner ever was in Rhodesia. Although her husband's edition of her Letters includes three which cover this journey (Cronwright-Schreiner 1924a), he makes no mention of it in his Life (1924), and it is not touched on either in First and Scott (1980) or in Stanley's impressive biographical chapter (2002). Arguably, it does nothing to alter the by now well-established outlines of Olive Schreiner's life; yet, as we shall see, the visit itself might have meant the premature end of that life. Moreover, it documents Schreiner's visit to two sites of immense importance to her : the 'Hanging Tree' in Bulawayo which features in the (deliberately shocking) photographic frontispiece to the first edition of Trooper Peter Halket of Mashonaland (1897), and, secondly, Cecil Rhodes's grave in the Matopos. In just over a decade (13 Aug. 1921), she too would lie in her chosen mountaintop tomb.
- Full Text:
- Date Issued: 2007
Patterns and processes underlying evolutionary significant units in the Platypleura stridula L. species complex (Hemiptera: Cicadidae) in the Cape Floristic Region, South Africa
- Price, Benjamin W, Barker, Nigel P, Villet, Martin H
- Authors: Price, Benjamin W , Barker, Nigel P , Villet, Martin H
- Date: 2007
- Language: English
- Type: Article
- Identifier: vital:6964 , http://hdl.handle.net/10962/d1012027
- Description: Cicadas have been shown to be useful organisms for examining the effects of distribution, plant association and geographical barriers on gene flow between populations. The cicadas of the Platypleura stridula species complex are restricted to the biologically diverse Cape Floristic Region (CFR) of South Africa. They are thus an excellent study group for elucidating the mechanisms by which hemipteran diversity is generated and maintained in the CFR. Phylogeographical analysis of this species complex using mitochondrial DNA Cytochrome Oxidase I (COI) and ribosomal 16S sequence data, coupled with preliminary morphological and acoustic data, resolves six clades, each of which has specific host-plant associations and distinct geographical ranges. The phylogeographical structure implies simultaneous or near-simultaneous radiation events, coupled with shifts in host-plant associations. When calibrated using published COI and 16S substitution rates typical for related insects, these lineages date back to the late Pliocene - early Pleistocene, coincident with vegetation change, altered drainage patterns and accelerated erosion in response to neotectonic crustal uplift and cyclic Pleistocene climate change, and glaciation-associated changes in climate and sea level.
- Full Text:
- Date Issued: 2007
- Authors: Price, Benjamin W , Barker, Nigel P , Villet, Martin H
- Date: 2007
- Language: English
- Type: Article
- Identifier: vital:6964 , http://hdl.handle.net/10962/d1012027
- Description: Cicadas have been shown to be useful organisms for examining the effects of distribution, plant association and geographical barriers on gene flow between populations. The cicadas of the Platypleura stridula species complex are restricted to the biologically diverse Cape Floristic Region (CFR) of South Africa. They are thus an excellent study group for elucidating the mechanisms by which hemipteran diversity is generated and maintained in the CFR. Phylogeographical analysis of this species complex using mitochondrial DNA Cytochrome Oxidase I (COI) and ribosomal 16S sequence data, coupled with preliminary morphological and acoustic data, resolves six clades, each of which has specific host-plant associations and distinct geographical ranges. The phylogeographical structure implies simultaneous or near-simultaneous radiation events, coupled with shifts in host-plant associations. When calibrated using published COI and 16S substitution rates typical for related insects, these lineages date back to the late Pliocene - early Pleistocene, coincident with vegetation change, altered drainage patterns and accelerated erosion in response to neotectonic crustal uplift and cyclic Pleistocene climate change, and glaciation-associated changes in climate and sea level.
- Full Text:
- Date Issued: 2007
Phylogeographic structure of Octopus vulgaris in South Africa revisited: identification of a second lineage near Durban harbor
- Teske, Peter R, Oosthuizen, A, Papadopoulos, I, Barker, Nigel P
- Authors: Teske, Peter R , Oosthuizen, A , Papadopoulos, I , Barker, Nigel P
- Date: 2007
- Language: English
- Type: Article
- Identifier: vital:6544 , http://hdl.handle.net/10962/d1006000
- Description: In a previous study that investigated genetic structure of Octopus vulgaris along the South African coast by sequencing the mitochondrial cytochrome oxidase III gene (COIII), all sequences generated were identical. Such a finding is unusual, because mitochondrial DNA mutates quickly, and several marine invertebrates present in southern Africa show considerable genetic variation and structure. We reanalysed the samples using two different mitochondrial markers, namely cytochrome oxidase I (COI) and the large ribosomal subunit (16S rRNA). Sequences of both these markers showed variation. The conclusion of the previous study, that South Africa’s O. vulgaris population is characterised by a lack of genetic structure along the coast, is rejected. Some specimens from Durban (southeast Africa) were genetically more different from those found in the remainder of the country than were specimens from other regions (Tristan da Cunha and Senegal). We suggest that the lineage in Durban may have been recently introduced.
- Full Text:
- Date Issued: 2007
- Authors: Teske, Peter R , Oosthuizen, A , Papadopoulos, I , Barker, Nigel P
- Date: 2007
- Language: English
- Type: Article
- Identifier: vital:6544 , http://hdl.handle.net/10962/d1006000
- Description: In a previous study that investigated genetic structure of Octopus vulgaris along the South African coast by sequencing the mitochondrial cytochrome oxidase III gene (COIII), all sequences generated were identical. Such a finding is unusual, because mitochondrial DNA mutates quickly, and several marine invertebrates present in southern Africa show considerable genetic variation and structure. We reanalysed the samples using two different mitochondrial markers, namely cytochrome oxidase I (COI) and the large ribosomal subunit (16S rRNA). Sequences of both these markers showed variation. The conclusion of the previous study, that South Africa’s O. vulgaris population is characterised by a lack of genetic structure along the coast, is rejected. Some specimens from Durban (southeast Africa) were genetically more different from those found in the remainder of the country than were specimens from other regions (Tristan da Cunha and Senegal). We suggest that the lineage in Durban may have been recently introduced.
- Full Text:
- Date Issued: 2007
Physical and biological processes at the Subtropical Convergence in the South-west Indian Ocean
- Froneman, P William, Ansorge, Isabelle J, Richoux, Nicole B, Blake, Justin, Daly, Ryan, Sterley, Jessica A, Mostert, B, Heyns, Elodie R, Sheppard, Jill N, Kuyper, B, Hart, N, George, C, Howard, J, Mustafa, E, Pey, F, Lutjeharms, Johan R E
- Authors: Froneman, P William , Ansorge, Isabelle J , Richoux, Nicole B , Blake, Justin , Daly, Ryan , Sterley, Jessica A , Mostert, B , Heyns, Elodie R , Sheppard, Jill N , Kuyper, B , Hart, N , George, C , Howard, J , Mustafa, E , Pey, F , Lutjeharms, Johan R E
- Date: 2007
- Language: English
- Type: Article
- Identifier: vital:6966 , http://hdl.handle.net/10962/d1012030
- Description: A detailed hydrographic and biological survey was conducted in the region of the Subtropical Convergence in the Indian sector of the Southern Ocean in April 2007. Hydrographic data revealed that the subsurface expression of the Subtropical Convergence (at 200 m), marked by the 10°C isotherm, appeared to meander considerably between 41°S and 42°15’S. Total surface chlorophyll- a concentration was low and ranged from 0.03 to 0.42 µg l–1 and was always dominated by the pico- (<2 µm) and nano- (2–120 µm) size classes, which contributed between 81% and 93% of the total pigment. The total chlorophyll-a integrated over the top 150m of the water column showed no distinct spatial trends, and ranged from 12.8 to 40.1mg chl-a m–2. There were no significant correlations between the total integrated chlorophyll- a concentration and temperature and salinity (P > 0.05). The zooplankton community was dominated, numerically and by biomass, by mesozooplankton comprising mainly copepods of the genera, Oithona,Paraeuchaeta, Pleuromamma, Calanus and Clausocalanus. An exception was recorded at those stations in the region of the front where the tunicate, Salpa thompsoni, dominated the total zooplankton biomass.
- Full Text:
- Date Issued: 2007
- Authors: Froneman, P William , Ansorge, Isabelle J , Richoux, Nicole B , Blake, Justin , Daly, Ryan , Sterley, Jessica A , Mostert, B , Heyns, Elodie R , Sheppard, Jill N , Kuyper, B , Hart, N , George, C , Howard, J , Mustafa, E , Pey, F , Lutjeharms, Johan R E
- Date: 2007
- Language: English
- Type: Article
- Identifier: vital:6966 , http://hdl.handle.net/10962/d1012030
- Description: A detailed hydrographic and biological survey was conducted in the region of the Subtropical Convergence in the Indian sector of the Southern Ocean in April 2007. Hydrographic data revealed that the subsurface expression of the Subtropical Convergence (at 200 m), marked by the 10°C isotherm, appeared to meander considerably between 41°S and 42°15’S. Total surface chlorophyll- a concentration was low and ranged from 0.03 to 0.42 µg l–1 and was always dominated by the pico- (<2 µm) and nano- (2–120 µm) size classes, which contributed between 81% and 93% of the total pigment. The total chlorophyll-a integrated over the top 150m of the water column showed no distinct spatial trends, and ranged from 12.8 to 40.1mg chl-a m–2. There were no significant correlations between the total integrated chlorophyll- a concentration and temperature and salinity (P > 0.05). The zooplankton community was dominated, numerically and by biomass, by mesozooplankton comprising mainly copepods of the genera, Oithona,Paraeuchaeta, Pleuromamma, Calanus and Clausocalanus. An exception was recorded at those stations in the region of the front where the tunicate, Salpa thompsoni, dominated the total zooplankton biomass.
- Full Text:
- Date Issued: 2007
Physical implications of prolonged sitting in a confined posture - a literature review
- Todd, Andrew I, Bennett, Anthea I, Christie, Candice J
- Authors: Todd, Andrew I , Bennett, Anthea I , Christie, Candice J
- Date: 2007
- Language: English
- Type: Article
- Identifier: vital:6756 , http://hdl.handle.net/10962/d1009458
- Description: The main purpose of this review article was to highlight some of the physical consequences of sitting for prolonged periods in a confined setting. More specifically, the review relates this research to call centre work and where applicable comments on the limited literature relating specifically to ergonomics research within call centre settings. In particular the article explores the biomechanical stresses placed on the musculoskeletal system during prolonged sitting at a workstation, and the physiological consequences thereof. The paper then provides possible solutions to reduce the physical strain placed on these workers by looking at workstation design and work organisation emphasizing worker education and the promotion of worker well being.
- Full Text:
- Date Issued: 2007
- Authors: Todd, Andrew I , Bennett, Anthea I , Christie, Candice J
- Date: 2007
- Language: English
- Type: Article
- Identifier: vital:6756 , http://hdl.handle.net/10962/d1009458
- Description: The main purpose of this review article was to highlight some of the physical consequences of sitting for prolonged periods in a confined setting. More specifically, the review relates this research to call centre work and where applicable comments on the limited literature relating specifically to ergonomics research within call centre settings. In particular the article explores the biomechanical stresses placed on the musculoskeletal system during prolonged sitting at a workstation, and the physiological consequences thereof. The paper then provides possible solutions to reduce the physical strain placed on these workers by looking at workstation design and work organisation emphasizing worker education and the promotion of worker well being.
- Full Text:
- Date Issued: 2007
Poets and the bells of Shandon
- Authors: Lewis, Colin A
- Date: 2007
- Language: English
- Type: Article
- Identifier: vital:6176 , http://hdl.handle.net/10962/d1012369 , http://www.ringingworld.co.uk
- Description: Colin Lewis was Professor of Geography at Rhodes University, Grahamstown, South Africa from 1989 until his retirement at the end of 2007. In 1990, with the strong support of the incumbent Vice-Chancellor, Dr Derek Henderson, he instigated the Certificate in Change Ringing (Church Bell Ringing) in the Rhodes University Department of Music and Musicology - the first such course to be offered in Africa. Since that date he has lectured in the basic theory, and taught the practice of change ringing. He is the Ringing Master of the Cathedral of St Michael and St George, Grahamstown, South Africa.
- Full Text: false
- Date Issued: 2007
- Authors: Lewis, Colin A
- Date: 2007
- Language: English
- Type: Article
- Identifier: vital:6176 , http://hdl.handle.net/10962/d1012369 , http://www.ringingworld.co.uk
- Description: Colin Lewis was Professor of Geography at Rhodes University, Grahamstown, South Africa from 1989 until his retirement at the end of 2007. In 1990, with the strong support of the incumbent Vice-Chancellor, Dr Derek Henderson, he instigated the Certificate in Change Ringing (Church Bell Ringing) in the Rhodes University Department of Music and Musicology - the first such course to be offered in Africa. Since that date he has lectured in the basic theory, and taught the practice of change ringing. He is the Ringing Master of the Cathedral of St Michael and St George, Grahamstown, South Africa.
- Full Text: false
- Date Issued: 2007
Pretopological and topological lattice-valued convergence spaces
- Authors: Jäger, Gunter
- Date: 2007
- Language: English
- Type: text , Article
- Identifier: vital:6827 , http://hdl.handle.net/10962/d1012337
- Description: We show that the classical axiom which characterizes pretopological convergence spaces splits into two axioms in the general Heyting algebra-valued case. Furthermore we present a generalization of Kowalski’s diagonal condition to the lattice-valued case.
- Full Text:
- Date Issued: 2007
- Authors: Jäger, Gunter
- Date: 2007
- Language: English
- Type: text , Article
- Identifier: vital:6827 , http://hdl.handle.net/10962/d1012337
- Description: We show that the classical axiom which characterizes pretopological convergence spaces splits into two axioms in the general Heyting algebra-valued case. Furthermore we present a generalization of Kowalski’s diagonal condition to the lattice-valued case.
- Full Text:
- Date Issued: 2007
Quality of life in South Africa: the first ten years of democracy
- Authors: Moller, Valerie
- Date: 2007
- Language: English
- Type: Article
- Identifier: vital:7110 , http://hdl.handle.net/10962/d1010741
- Description: South Africa celebrated ten years of democracy in 2004. This special issue of Social Indicators Research (SIR) reviews developments that have impacted on the quality of life of ordinary South Africans during the transition period. The issue updates an earlier volume of SIR (Volume 41) published in 1997 and as a stand-alone volume. The earlier volume was initiated following SIR editor Alex Michalos’ first visit to South Africa. This update on quality of life in South Africa follows on his return visit to the country in 2004 to see firsthand the changes that had occured in the meantime. This introductory article outlines major achievements of and setbacks for the new democracy and the challenges facing it in future. It provides the backround for the evaluations of a range of quality of life domains and issues including poverty and inequality, crime, the HIV/AIDS epidemic, migration and housing, religiosity, reconciliation, and optimism for the future which are covered in the eleven articles that follow. The introduction divides the articles under the headings of challenges, achievements, monitoring quality of life, and social capital for the future. The overview article concludes that improvements in quality of life have been uneven but goodwill and a positive outlook bode well for South African quality of life in future.
- Full Text:
- Date Issued: 2007
- Authors: Moller, Valerie
- Date: 2007
- Language: English
- Type: Article
- Identifier: vital:7110 , http://hdl.handle.net/10962/d1010741
- Description: South Africa celebrated ten years of democracy in 2004. This special issue of Social Indicators Research (SIR) reviews developments that have impacted on the quality of life of ordinary South Africans during the transition period. The issue updates an earlier volume of SIR (Volume 41) published in 1997 and as a stand-alone volume. The earlier volume was initiated following SIR editor Alex Michalos’ first visit to South Africa. This update on quality of life in South Africa follows on his return visit to the country in 2004 to see firsthand the changes that had occured in the meantime. This introductory article outlines major achievements of and setbacks for the new democracy and the challenges facing it in future. It provides the backround for the evaluations of a range of quality of life domains and issues including poverty and inequality, crime, the HIV/AIDS epidemic, migration and housing, religiosity, reconciliation, and optimism for the future which are covered in the eleven articles that follow. The introduction divides the articles under the headings of challenges, achievements, monitoring quality of life, and social capital for the future. The overview article concludes that improvements in quality of life have been uneven but goodwill and a positive outlook bode well for South African quality of life in future.
- Full Text:
- Date Issued: 2007
Re-examining ‘professionalism’ in pharmacy: a South African perspective
- Authors: Williams, K F
- Date: 2007
- Language: English
- Type: Article
- Identifier: vital:6084 , http://hdl.handle.net/10962/d1008481 , http://dx.doi.org/10.1016/j.socscimed.2006.11.001
- Description: Although defining itself as a patient-centred profession, private sector (community and private hospital) pharmacy often appears to be that of a product-for-profit centred occupation. This perception has been at the core of the medical profession's attempts to reduce the professional autonomy of pharmacy, and has appeared at the forefront of the South African Department of Health's positioning of private sector pharmacy. Using as a starting point the debate surrounding attempts by the South African Minister of Health to regulate the price of medicines, I propose that the present negative positioning of private sector pharmacy in South Africa could be ameliorated by pharmacy practice that evidences a redefined understanding of professionalism.
- Full Text:
- Date Issued: 2007
- Authors: Williams, K F
- Date: 2007
- Language: English
- Type: Article
- Identifier: vital:6084 , http://hdl.handle.net/10962/d1008481 , http://dx.doi.org/10.1016/j.socscimed.2006.11.001
- Description: Although defining itself as a patient-centred profession, private sector (community and private hospital) pharmacy often appears to be that of a product-for-profit centred occupation. This perception has been at the core of the medical profession's attempts to reduce the professional autonomy of pharmacy, and has appeared at the forefront of the South African Department of Health's positioning of private sector pharmacy. Using as a starting point the debate surrounding attempts by the South African Minister of Health to regulate the price of medicines, I propose that the present negative positioning of private sector pharmacy in South Africa could be ameliorated by pharmacy practice that evidences a redefined understanding of professionalism.
- Full Text:
- Date Issued: 2007