Over-expression, purification and biochemical characterisation of trypanosomal heat shock protein
- Authors: Edkins, Adrienne Lesley
- Date: 2003
- Subjects: Heat shock proteins , Heat shock proteins -- Structure activity relationships
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4106 , http://hdl.handle.net/10962/d1011736 , Heat shock proteins , Heat shock proteins -- Structure activity relationships
- Description: The molecular chaperone process of assisted protein folding, characteristic of members of the Heat Shock Protein 70 kDa (Hsp70) and Heat Shock Protein 40kDa (Hsp40) families, is essential for cytoprotection in stressful cellular conditions. Examples of such conditions are heat shock or invasion by pathogens. The Hsp70/Hsp40 process of assisted protein folding is dependent on ATP (governed by the intrinsic ATPase activity of Hsp70) and the ability of molecular chaperones to recognise and bind non-native protein conformations. Here, we analyse and attempt to characterise the molecular chaperone activity of an inducible, cytoplasmic Hsp70 (TcHsp70) from Trypanosoma cruzi and its interactions with its potential partner Hsp40s, Tcj 1, Tcj2, Tcj3 and Tcj4. A bioinformatic analyses of the primary sequences of the trypanosomal proteins revealed that they all contained the canonical domains that define other members of the Hsp70 and Hsp40 family. Tcj2 and Tcj4 showed deviations from the consensus sequence in their substrate binding regions, which may have implications for their substrate binding specificities. TcHsp70, Tcj 1, Tcj2, Tcj3 and Tcj4 were over-expressed recombinantly as 6xHis-tag fusion proteins in Escherichia coli. His-TcHsp70, Tcjl-His and His-Tcj2 were successfully purified by Nickel-affinity chromatography for functional analyses to assess the molecular chaperone activity of His-TcHsp70 in terms of its ATPase activity and substrate binding ability. The basal ATPase activity of His-TcHsp70 was determined as 40 nmol Pi/min/mg, significantly higher than that reported for other Hsp70s. This basal ATPase activity was stimulated to a maximal level of 60 nmol Pi/min/mg in the presence of His-Tcj2 and a model non-native substrate, reduced carboxymethylated αx-lactalbumin (RCMLA). Using native polyacrylamide gel electrophoresis and Western analysis, His-TcHsp70 was shown to form discrete complexes when in the presence of Tcj 1- His, His-Tcj2 and/or RCMLA. These complexes potentially represent His-TcHsp70 - RCMLA or His-TcHsp70 - Tcj interactions, that may be indicative of chaperone activity. In vivo complementation assays showed that Tcj2, but not Tcj3, was able to overcome the temperature sensitivity of the ydjJ mutant Saccharomyces cerevisiae strain JJ160, suggesting that Tcj2 may be functionally equivalent to the yeast Hsp40 Ydj1.
- Full Text:
- Date Issued: 2003
- Authors: Edkins, Adrienne Lesley
- Date: 2003
- Subjects: Heat shock proteins , Heat shock proteins -- Structure activity relationships
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4106 , http://hdl.handle.net/10962/d1011736 , Heat shock proteins , Heat shock proteins -- Structure activity relationships
- Description: The molecular chaperone process of assisted protein folding, characteristic of members of the Heat Shock Protein 70 kDa (Hsp70) and Heat Shock Protein 40kDa (Hsp40) families, is essential for cytoprotection in stressful cellular conditions. Examples of such conditions are heat shock or invasion by pathogens. The Hsp70/Hsp40 process of assisted protein folding is dependent on ATP (governed by the intrinsic ATPase activity of Hsp70) and the ability of molecular chaperones to recognise and bind non-native protein conformations. Here, we analyse and attempt to characterise the molecular chaperone activity of an inducible, cytoplasmic Hsp70 (TcHsp70) from Trypanosoma cruzi and its interactions with its potential partner Hsp40s, Tcj 1, Tcj2, Tcj3 and Tcj4. A bioinformatic analyses of the primary sequences of the trypanosomal proteins revealed that they all contained the canonical domains that define other members of the Hsp70 and Hsp40 family. Tcj2 and Tcj4 showed deviations from the consensus sequence in their substrate binding regions, which may have implications for their substrate binding specificities. TcHsp70, Tcj 1, Tcj2, Tcj3 and Tcj4 were over-expressed recombinantly as 6xHis-tag fusion proteins in Escherichia coli. His-TcHsp70, Tcjl-His and His-Tcj2 were successfully purified by Nickel-affinity chromatography for functional analyses to assess the molecular chaperone activity of His-TcHsp70 in terms of its ATPase activity and substrate binding ability. The basal ATPase activity of His-TcHsp70 was determined as 40 nmol Pi/min/mg, significantly higher than that reported for other Hsp70s. This basal ATPase activity was stimulated to a maximal level of 60 nmol Pi/min/mg in the presence of His-Tcj2 and a model non-native substrate, reduced carboxymethylated αx-lactalbumin (RCMLA). Using native polyacrylamide gel electrophoresis and Western analysis, His-TcHsp70 was shown to form discrete complexes when in the presence of Tcj 1- His, His-Tcj2 and/or RCMLA. These complexes potentially represent His-TcHsp70 - RCMLA or His-TcHsp70 - Tcj interactions, that may be indicative of chaperone activity. In vivo complementation assays showed that Tcj2, but not Tcj3, was able to overcome the temperature sensitivity of the ydjJ mutant Saccharomyces cerevisiae strain JJ160, suggesting that Tcj2 may be functionally equivalent to the yeast Hsp40 Ydj1.
- Full Text:
- Date Issued: 2003
Paranoid metaphors: an examination of the discursive, theoretical and sometimes personal, interaction between the psychoanalyst, Jacques Lacan, the surrealist, Salvador Dali, and the English poet, David Gascoyne
- Authors: De Klerk, Eugene
- Date: 2003
- Subjects: Paranoia , Lacan, Jacques, 1901-1981 , Dali, Salvador, 1904-1989 , Gascoyne, David, 1916-2001
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2192 , http://hdl.handle.net/10962/d1002234 , Paranoia , Lacan, Jacques, 1901-1981 , Dali, Salvador, 1904-1989 , Gascoyne, David, 1916-2001
- Description: This thesis examines the historical interaction of the psychoanalyst, Jacques Lacan, the surrealist, Salvador Dali, and the English poet, David Gascoyne. It traces the discursive, and sometimes personal, relationship between these figures which led to a psychoanalytic-based conception of paranoia that impacted on both surrealism and the surrealist-inspired poetry and theory of David Gascoyne. Furthermore it seeks to identify the potential ramifications of this conception of paranoia, and the artistic practice it engendered, for literary, Marxist and psychoanalytic theory.
- Full Text:
- Date Issued: 2003
- Authors: De Klerk, Eugene
- Date: 2003
- Subjects: Paranoia , Lacan, Jacques, 1901-1981 , Dali, Salvador, 1904-1989 , Gascoyne, David, 1916-2001
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2192 , http://hdl.handle.net/10962/d1002234 , Paranoia , Lacan, Jacques, 1901-1981 , Dali, Salvador, 1904-1989 , Gascoyne, David, 1916-2001
- Description: This thesis examines the historical interaction of the psychoanalyst, Jacques Lacan, the surrealist, Salvador Dali, and the English poet, David Gascoyne. It traces the discursive, and sometimes personal, relationship between these figures which led to a psychoanalytic-based conception of paranoia that impacted on both surrealism and the surrealist-inspired poetry and theory of David Gascoyne. Furthermore it seeks to identify the potential ramifications of this conception of paranoia, and the artistic practice it engendered, for literary, Marxist and psychoanalytic theory.
- Full Text:
- Date Issued: 2003
Participants' perceptions of Computer-Mediated Communication: a case study of the Global Teenager Project
- Authors: Turyagyenda, Joy Kyarimpa
- Date: 2003
- Subjects: Global Teenager Project Computer networks -- Social aspects Communication Telematics Learning -- Technological innovations
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1687 , http://hdl.handle.net/10962/d1003570
- Description: The study outlines general trends evident in Computer-Mediated Communication (CMC), participants’ perceptions and the promotion of CMC across the curriculum in a South African Secondary School. This case study focuses on the Global Teenager Project (GTP), which started as a bi-national pilot project in April 1999 between secondary schools in South Africa and the Netherlands. The study sets out to investigate how well the GTP can be incorporated into the existing school curriculum through the teacherresearcher’s direct involvement in facilitating the project at a school where she is a fulltime teacher. The main purpose of the study is to review existing literature to establish how collaborative learning could be achieved through a CMC environment between teenagers from various countries based on the research done at an international level and link the practice at this school to the existing international trends. It was found that the GTP has great potential in enhancing collaborative learning within various learning areas at Nathaniel Nyaluza Secondary School (NNSS). Despite the usefulness of the GTP and the overwhelming enthusiasm learners displayed, its success at NNSS depended on the motivation of teachers and how easily the activities of the GTP could be incorporated within day-to-day teachers’ activities. , Hodgkinson, Cheryl
- Full Text:
- Date Issued: 2003
- Authors: Turyagyenda, Joy Kyarimpa
- Date: 2003
- Subjects: Global Teenager Project Computer networks -- Social aspects Communication Telematics Learning -- Technological innovations
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1687 , http://hdl.handle.net/10962/d1003570
- Description: The study outlines general trends evident in Computer-Mediated Communication (CMC), participants’ perceptions and the promotion of CMC across the curriculum in a South African Secondary School. This case study focuses on the Global Teenager Project (GTP), which started as a bi-national pilot project in April 1999 between secondary schools in South Africa and the Netherlands. The study sets out to investigate how well the GTP can be incorporated into the existing school curriculum through the teacherresearcher’s direct involvement in facilitating the project at a school where she is a fulltime teacher. The main purpose of the study is to review existing literature to establish how collaborative learning could be achieved through a CMC environment between teenagers from various countries based on the research done at an international level and link the practice at this school to the existing international trends. It was found that the GTP has great potential in enhancing collaborative learning within various learning areas at Nathaniel Nyaluza Secondary School (NNSS). Despite the usefulness of the GTP and the overwhelming enthusiasm learners displayed, its success at NNSS depended on the motivation of teachers and how easily the activities of the GTP could be incorporated within day-to-day teachers’ activities. , Hodgkinson, Cheryl
- Full Text:
- Date Issued: 2003
Patents, pills, poverty and pandemic: the ethical issues
- Authors: Brown, Walter
- Date: 2003
- Subjects: Kant, Immanuel, 1724-1804 -- Ethics , AIDS (Disease) -- Treatment -- South Africa -- Moral and ethical aspects , AIDS (Disease) -- Moral and ethical aspects , HIV infections -- South Africa , HIV infections -- Treatment -- South Africa -- Moral and ethical aspects , Social responsibility of business , Pharmaceutical industry -- South Africa -- Moral and ethical aspects
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2705 , http://hdl.handle.net/10962/d1002835 , Kant, Immanuel, 1724-1804 -- Ethics , AIDS (Disease) -- Treatment -- South Africa -- Moral and ethical aspects , AIDS (Disease) -- Moral and ethical aspects , HIV infections -- South Africa , HIV infections -- Treatment -- South Africa -- Moral and ethical aspects , Social responsibility of business , Pharmaceutical industry -- South Africa -- Moral and ethical aspects
- Description: This thesis argues that corporations qua corporations are moral agents sui generis and hence capable of being held morally responsible. I argue that corporations qua corporations are responsible for the actual and foreseen consequences of their actions. I analyse normative theories and the different proscriptive responsibilities they place on moral agents and hence corporations. I examine Kantianism, utilitarianism and virtue ethics. I argue for a unique normative ethical theory that incorporates reasoning from all three of the normative theories. I argue for a broad range of reasons to factor into deciding whether an act is ethical or not. One of the claims of this thesis is that ethical theories must incorporate an agent’s motivation, intention and character traits as relevant to deciding on whether an action is ethical or not. My thesis argues for an indispensable role for the virtues while at the same time incorporating impartial beneficence and universal rationality from utilitarianism and Kantianism. This position I, following the literature, refer to as moderate virtue theory. Having established corporate qua corporate responsibility I question the pharmaceutical corporation’s practice of patenting life saving medication during a state of pandemic in poor countries. The moderate virtue theory position prioritises contexts and the actual human condition and criticises normative theories that attempt to give universal, abstracted answers to ethical problems. It is for this reason and the current (2003) HIV/AIDS pandemic that I focus on a particular context. I examine the practice of patenting life saving medication within South Africa and argue, applying moderate virtue theory, that this act cannot be justified. I argue that a pharmaceutical corporation that patents life saving medication in South Africa cannot justify that action and thus is morally responsible for that action. I also argue that corporations patenting HIV/AIDS medication in South Africa have unethical motivations and intentions.
- Full Text:
- Date Issued: 2003
- Authors: Brown, Walter
- Date: 2003
- Subjects: Kant, Immanuel, 1724-1804 -- Ethics , AIDS (Disease) -- Treatment -- South Africa -- Moral and ethical aspects , AIDS (Disease) -- Moral and ethical aspects , HIV infections -- South Africa , HIV infections -- Treatment -- South Africa -- Moral and ethical aspects , Social responsibility of business , Pharmaceutical industry -- South Africa -- Moral and ethical aspects
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2705 , http://hdl.handle.net/10962/d1002835 , Kant, Immanuel, 1724-1804 -- Ethics , AIDS (Disease) -- Treatment -- South Africa -- Moral and ethical aspects , AIDS (Disease) -- Moral and ethical aspects , HIV infections -- South Africa , HIV infections -- Treatment -- South Africa -- Moral and ethical aspects , Social responsibility of business , Pharmaceutical industry -- South Africa -- Moral and ethical aspects
- Description: This thesis argues that corporations qua corporations are moral agents sui generis and hence capable of being held morally responsible. I argue that corporations qua corporations are responsible for the actual and foreseen consequences of their actions. I analyse normative theories and the different proscriptive responsibilities they place on moral agents and hence corporations. I examine Kantianism, utilitarianism and virtue ethics. I argue for a unique normative ethical theory that incorporates reasoning from all three of the normative theories. I argue for a broad range of reasons to factor into deciding whether an act is ethical or not. One of the claims of this thesis is that ethical theories must incorporate an agent’s motivation, intention and character traits as relevant to deciding on whether an action is ethical or not. My thesis argues for an indispensable role for the virtues while at the same time incorporating impartial beneficence and universal rationality from utilitarianism and Kantianism. This position I, following the literature, refer to as moderate virtue theory. Having established corporate qua corporate responsibility I question the pharmaceutical corporation’s practice of patenting life saving medication during a state of pandemic in poor countries. The moderate virtue theory position prioritises contexts and the actual human condition and criticises normative theories that attempt to give universal, abstracted answers to ethical problems. It is for this reason and the current (2003) HIV/AIDS pandemic that I focus on a particular context. I examine the practice of patenting life saving medication within South Africa and argue, applying moderate virtue theory, that this act cannot be justified. I argue that a pharmaceutical corporation that patents life saving medication in South Africa cannot justify that action and thus is morally responsible for that action. I also argue that corporations patenting HIV/AIDS medication in South Africa have unethical motivations and intentions.
- Full Text:
- Date Issued: 2003
Patterns of early adolescent sex and implications for HIV/AIDS risk prevention : a contextual study in the Amatole Basin, Eastern Cape
- Authors: Ntlabati, Pumla L
- Date: 2003
- Subjects: Teenagers -- Sexual behavior , Teenagers -- Health and hygiene -- South Africa -- Eastern Cape , Teenagers -- Diseases -- South Africa -- Eastern Cape , Sexually transmitted diseases -- South Africa -- Eastern Cape , AIDS (Disease) -- South Africa -- Eastern Cape , AIDS (Disease) in adolescence -- South Africa -- Eastern Cape -- Attitudes , AIDS (Disease) -- Prevention -- South Africa --Eastern Cape
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:3176 , http://hdl.handle.net/10962/d1007814
- Description: This study involves an analysis of accounts of first and subsequent early sexual experiences in a deep rural area of the Eastern Cape in South Africa over the last forty years. Through interviews and focus group discussions, the enculturation of youth into sexual activity in the community of interest is explored. The study looks into sexual experiences from childhood, through early adolescence to adults of up to sixty five years old, allowing an analysis of the changing forms of sexual experimentation and sexual debut in this context. Contextual factors mediating these changes are explored, with special emphasis on the changing regulatory practices around early sexual experiences and the effect thereof on behaviors connected to HIV infection risk. Practices that were previously important mediators of sexual behavior were: anxiety about the social consequences of pregnancy, which was previously a significant disincentive to sexual intercourse; men's previous acceptance of the need to practice non-penetrative forms of sex and girls postponing sexual debut for as long as possible. All these were culturally endorsed, but are now noted to have changed due to changes in the regulatory practices surrounding youth sexuality. The context of early sexual experiences and the surrounding cultural practices have also changed significantly, and this needs to be taken into account in understanding receptivity to condom use messages. Implications for HIV/AIDS prevention are discussed. Among other interventions, the study describes a participatory, community-based, multi-sectoral approach that takes social conditions into account as a way of empowering the community to strengthen its response to the pandemic. This incorporates different sectors of the community, including youth, parents, religious and traditional leaders, and various other structures, services and institutions that make up the community.
- Full Text:
- Date Issued: 2003
- Authors: Ntlabati, Pumla L
- Date: 2003
- Subjects: Teenagers -- Sexual behavior , Teenagers -- Health and hygiene -- South Africa -- Eastern Cape , Teenagers -- Diseases -- South Africa -- Eastern Cape , Sexually transmitted diseases -- South Africa -- Eastern Cape , AIDS (Disease) -- South Africa -- Eastern Cape , AIDS (Disease) in adolescence -- South Africa -- Eastern Cape -- Attitudes , AIDS (Disease) -- Prevention -- South Africa --Eastern Cape
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:3176 , http://hdl.handle.net/10962/d1007814
- Description: This study involves an analysis of accounts of first and subsequent early sexual experiences in a deep rural area of the Eastern Cape in South Africa over the last forty years. Through interviews and focus group discussions, the enculturation of youth into sexual activity in the community of interest is explored. The study looks into sexual experiences from childhood, through early adolescence to adults of up to sixty five years old, allowing an analysis of the changing forms of sexual experimentation and sexual debut in this context. Contextual factors mediating these changes are explored, with special emphasis on the changing regulatory practices around early sexual experiences and the effect thereof on behaviors connected to HIV infection risk. Practices that were previously important mediators of sexual behavior were: anxiety about the social consequences of pregnancy, which was previously a significant disincentive to sexual intercourse; men's previous acceptance of the need to practice non-penetrative forms of sex and girls postponing sexual debut for as long as possible. All these were culturally endorsed, but are now noted to have changed due to changes in the regulatory practices surrounding youth sexuality. The context of early sexual experiences and the surrounding cultural practices have also changed significantly, and this needs to be taken into account in understanding receptivity to condom use messages. Implications for HIV/AIDS prevention are discussed. Among other interventions, the study describes a participatory, community-based, multi-sectoral approach that takes social conditions into account as a way of empowering the community to strengthen its response to the pandemic. This incorporates different sectors of the community, including youth, parents, religious and traditional leaders, and various other structures, services and institutions that make up the community.
- Full Text:
- Date Issued: 2003
Peals in Africa
- Authors: Lewis, Colin A
- Date: 2003
- Language: English
- Type: Article
- Identifier: vital:6166 , http://hdl.handle.net/10962/d1012354
- 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: 2003
- Authors: Lewis, Colin A
- Date: 2003
- Language: English
- Type: Article
- Identifier: vital:6166 , http://hdl.handle.net/10962/d1012354
- 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: 2003
People-centred development in practice: the case of the Zikhova-Ngqinisa Sidibene Woodlot Trust Project
- Authors: Pona, Faith Zolisa
- Date: 2003
- Subjects: Zikhova-Ngqinisa Sidibene Woodlot Trust Project , Rural development -- South Africa -- Eastern Cape , Rural development projects -- South Africa -- Eastern Cape -- Citizen participation , Woodlots -- South Africa -- Eastern Cape , Economic development projects -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:3356 , http://hdl.handle.net/10962/d1007610 , Zikhova-Ngqinisa Sidibene Woodlot Trust Project , Rural development -- South Africa -- Eastern Cape , Rural development projects -- South Africa -- Eastern Cape -- Citizen participation , Woodlots -- South Africa -- Eastern Cape , Economic development projects -- South Africa -- Eastern Cape
- Description: This study addresses the question of people-centred development as a transformative aspect of the new South African development arena. The concept is defined as the involvement and active participation of people in the decision-making, evaluation and implementation of the development processes, It is one of the forms of democratisation which involves the decentralisaton of authority to the lower tiers of government. This study provides an analysis of the efficacy, relevance, advantages and disadvantages of people-centred development in the South African context. The Zikhoya-Ngqinisa Woodlot Trust Project was chosen as a case study, The reason was that through the process of devolution of the Department of Forestry and Water Affairs (DWAF), which involved the handing over of the management and financial resources of the small woodlots to the communities for their own benefit, the two villages, Zikhova and Ngqinisa, were given the Zikhova woodlot. The devolution of DWAF is one of the various forms of decentralisation that has given more autonomy to the lower tiers of government in the sense that the communities now have to satisfy their own needs. The main focus of the study was to identify and analyse constraints on the implementation of people-centred development specific to the Zikhova-Ngqinisa Woodlot Trust Project. Other interrelated aspects of people-centred development such as sustainability, community involvement and benefits of the project were also investigated and analysed. , KMBT_363
- Full Text:
- Date Issued: 2003
- Authors: Pona, Faith Zolisa
- Date: 2003
- Subjects: Zikhova-Ngqinisa Sidibene Woodlot Trust Project , Rural development -- South Africa -- Eastern Cape , Rural development projects -- South Africa -- Eastern Cape -- Citizen participation , Woodlots -- South Africa -- Eastern Cape , Economic development projects -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:3356 , http://hdl.handle.net/10962/d1007610 , Zikhova-Ngqinisa Sidibene Woodlot Trust Project , Rural development -- South Africa -- Eastern Cape , Rural development projects -- South Africa -- Eastern Cape -- Citizen participation , Woodlots -- South Africa -- Eastern Cape , Economic development projects -- South Africa -- Eastern Cape
- Description: This study addresses the question of people-centred development as a transformative aspect of the new South African development arena. The concept is defined as the involvement and active participation of people in the decision-making, evaluation and implementation of the development processes, It is one of the forms of democratisation which involves the decentralisaton of authority to the lower tiers of government. This study provides an analysis of the efficacy, relevance, advantages and disadvantages of people-centred development in the South African context. The Zikhoya-Ngqinisa Woodlot Trust Project was chosen as a case study, The reason was that through the process of devolution of the Department of Forestry and Water Affairs (DWAF), which involved the handing over of the management and financial resources of the small woodlots to the communities for their own benefit, the two villages, Zikhova and Ngqinisa, were given the Zikhova woodlot. The devolution of DWAF is one of the various forms of decentralisation that has given more autonomy to the lower tiers of government in the sense that the communities now have to satisfy their own needs. The main focus of the study was to identify and analyse constraints on the implementation of people-centred development specific to the Zikhova-Ngqinisa Woodlot Trust Project. Other interrelated aspects of people-centred development such as sustainability, community involvement and benefits of the project were also investigated and analysed. , KMBT_363
- Full Text:
- Date Issued: 2003
Personality traits of patients participating in a group programme at a private psychiatric day clinic
- Authors: Oakes, Elizabeth Jean
- Date: 2003
- Subjects: Personality assessment -- South Africa -- Port Elizabeth , NEO Personality Inventory -- South Africa -- Port Elizabeth , Psychotherapy -- Outcome assessment -- South Africa -- Port Elizabeth
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:11028 , http://hdl.handle.net/10948/331 , Personality assessment -- South Africa -- Port Elizabeth , NEO Personality Inventory -- South Africa -- Port Elizabeth , Psychotherapy -- Outcome assessment -- South Africa -- Port Elizabeth
- Description: The current trend in psychiatric health care is towards comprehensive primary healthcare for all South Africans. This has been has been achieved by the restructuring of the National Health System (NHS) into national, provincial, district, and community levels, which provide outpatient and inpatient care at primary, secondary, and tertiary care levels. Assessment and treatment in the form of physical and psychosocial interventions form an integral part of psychiatric care. The value of personality assessment and, in particular, the potential for matching patient personality types with effective treatment options, may play a role in facilitating effective health care in the future. An overview of the literature indicates that little research has been done regarding the area of personality traits of psychiatric patients in South Africa. This study aims to explore and describe the personality traits or profile of individuals attending a private psychiatric day care facility in The Nelson Mandela Metropole (i.e., Parkwood Day Clinic). The sample consisted of 196 participants (104 male and 92 female) who attended a group programme from April 2000 to April 2001. As part of the programme, patients were required to com plete a series of pencil-and-paper measures. The questionnaires selected for this study included a biographical questionnaire, which was used to describe the biographical variables of the sample with regard to gender, age and marital status, and The Revised NEO Personality Inventory (NEO PI-R) (Costa & McCrae, 1992a), which was used as a measure of personality. The NEO PI-R is considered a concise measure of the five major domains of personality and some of the more important traits that define each domain. Together, the five domains Neuroticism (N), Extraversion (E), Openness (O), Agreeableness (A) and Conscientiousness (C), and the six facets within each domain, allow for a comprehensive assessment of adult personality. xiv An exploratory, descriptive method was used in the study, and the data was analysed using descriptive and inferential statistics, including correlations, cluster analysis, and multivariate analysis of variance. Key findings include the following: Results from the NEO PI-R domains showed a personality profile of very high scores for N, and average scores for E, O, A, and C. Within the sample, cluster analysis revealed five distinct personality profile clusters. For the biographical variable gender, significant differences were found between males and females on N, with the majority of males scoring in the category of Very High and High, and the majority of females scoring in the Average category. For the variable age, the results indicated significant differences on A, with participants in the young adulthood group scoring significantly lower on A than participants in the middle adulthood group. For marital status, on the domain of O, significant differences were found between the divorced or widowed and the married, with the married scoring in the Low category and the divorced or widowed in the Average category. On the domain of C, significant differences were noted between the singles group and the currently or previously married groups, with the single group tending to score lower on C than both other groups. These findings reveal a need for further research into personality traits and psychiatric samples, as consideration of personality traits based on the profile established, may be useful in matching patients’ characteristics with optimal treatment options.
- Full Text:
- Date Issued: 2003
- Authors: Oakes, Elizabeth Jean
- Date: 2003
- Subjects: Personality assessment -- South Africa -- Port Elizabeth , NEO Personality Inventory -- South Africa -- Port Elizabeth , Psychotherapy -- Outcome assessment -- South Africa -- Port Elizabeth
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:11028 , http://hdl.handle.net/10948/331 , Personality assessment -- South Africa -- Port Elizabeth , NEO Personality Inventory -- South Africa -- Port Elizabeth , Psychotherapy -- Outcome assessment -- South Africa -- Port Elizabeth
- Description: The current trend in psychiatric health care is towards comprehensive primary healthcare for all South Africans. This has been has been achieved by the restructuring of the National Health System (NHS) into national, provincial, district, and community levels, which provide outpatient and inpatient care at primary, secondary, and tertiary care levels. Assessment and treatment in the form of physical and psychosocial interventions form an integral part of psychiatric care. The value of personality assessment and, in particular, the potential for matching patient personality types with effective treatment options, may play a role in facilitating effective health care in the future. An overview of the literature indicates that little research has been done regarding the area of personality traits of psychiatric patients in South Africa. This study aims to explore and describe the personality traits or profile of individuals attending a private psychiatric day care facility in The Nelson Mandela Metropole (i.e., Parkwood Day Clinic). The sample consisted of 196 participants (104 male and 92 female) who attended a group programme from April 2000 to April 2001. As part of the programme, patients were required to com plete a series of pencil-and-paper measures. The questionnaires selected for this study included a biographical questionnaire, which was used to describe the biographical variables of the sample with regard to gender, age and marital status, and The Revised NEO Personality Inventory (NEO PI-R) (Costa & McCrae, 1992a), which was used as a measure of personality. The NEO PI-R is considered a concise measure of the five major domains of personality and some of the more important traits that define each domain. Together, the five domains Neuroticism (N), Extraversion (E), Openness (O), Agreeableness (A) and Conscientiousness (C), and the six facets within each domain, allow for a comprehensive assessment of adult personality. xiv An exploratory, descriptive method was used in the study, and the data was analysed using descriptive and inferential statistics, including correlations, cluster analysis, and multivariate analysis of variance. Key findings include the following: Results from the NEO PI-R domains showed a personality profile of very high scores for N, and average scores for E, O, A, and C. Within the sample, cluster analysis revealed five distinct personality profile clusters. For the biographical variable gender, significant differences were found between males and females on N, with the majority of males scoring in the category of Very High and High, and the majority of females scoring in the Average category. For the variable age, the results indicated significant differences on A, with participants in the young adulthood group scoring significantly lower on A than participants in the middle adulthood group. For marital status, on the domain of O, significant differences were found between the divorced or widowed and the married, with the married scoring in the Low category and the divorced or widowed in the Average category. On the domain of C, significant differences were noted between the singles group and the currently or previously married groups, with the single group tending to score lower on C than both other groups. These findings reveal a need for further research into personality traits and psychiatric samples, as consideration of personality traits based on the profile established, may be useful in matching patients’ characteristics with optimal treatment options.
- Full Text:
- Date Issued: 2003
Pharmaceutical analysis and aspects of the quality control of St. John's Wort products
- Authors: Wild, Tracy Joy
- Date: 2003
- Subjects: Hypericum perforatum , Hypericum perforatum -- Analysis , Hypericum perforatum -- Therapeutic use , Hypericum perforatum -- Physiological effect , Flavonoids -- Analysis
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:3804 , http://hdl.handle.net/10962/d1003282 , Hypericum perforatum , Hypericum perforatum -- Analysis , Hypericum perforatum -- Therapeutic use , Hypericum perforatum -- Physiological effect , Flavonoids -- Analysis
- Description: Most complementary medicines contain a multitude of chemical components, some of which are claimed to contribute to the biological activity of such products. Use of complementary medicines for preventative and therapeutic purposes is increasing rapidly worldwide. Unfortunately, although control of these products is essential to ensure quality, safety, and efficacy, the quality control of most herbal preparations is currently poor to non-existent, with little or no safety and efficacy data required to support the marketing and use of these products. The objective of this study was therefore to develop suitable analytical methods to qualitatively and quantitatively analyse the relevant components (rutin, isoquercitrin, hyperoside, quercitrin, quercetin, kaempferol, hypericin, pseudohypericin and hyperforin) in St John's Wort dosage forms for quality control purposes. A gradient HPLC method using a Luna 5·mC₁₈(2) 150 x 2.00mm internal diameter (i.d.) column and UV detection, was developed for the separation of six of the relevant flavonoid compounds in St John's Wort, namely rutin, isoquercitrin, hyperoside, quercitrin, quercetin and kaempferol. The development process involved a systematic investigation of gradient conditions, flow rate, and temperature. This method was subsequently applied to assay selected commercially available St John's Wort products. This system provided the necessary accuracy, precision and reproducibility and was associated with several advantages when compared to using standard bore (4.60 mm i.d.) HPLC columns. The method developed is currently the only known method that separates all six relevant flavonoids in a reasonable run time (less than 20 minutes). It is also one of the few methods that has sufficient separation between rutin, isoquercitrin and hyperoside. A qualitative method for the fingerprinting of flavonoid components was also developed, using capillary electrophoresis (CE). CE is a rapidly growing powerful analytical technique for the separation of charged compounds. Micellar electrokinetic chromatography (MEKC) is a very powerful electrophoretic technique that is capable of selectively resolving both neutral and ionic solutes in a single run. A MEKC method suitable for the separation and determination of various flavonoid constituents used as marker compounds in Hypericum perforatum was developed. Investigations into the effect of pH, ionic strength, applied voltage and capillary dimensions on separation were performed. The optimised method was then applied to qualitatively analyse various St John's Wort products on the market. This method was found to be advantageous in that it was simple, cost-effective, required minimal sample preparation and utilised very small quantities of sample. Due to the vast differences in chemical properties between the various marker and active components in St John's Wort, it was necessary to develop separate analytical methods for the flavonoids and for the other three relevant compounds (hypericin, pseudohypericin and hyperforin). An isocratic HPLC method using a Luna 5·mC₁₈(2) 150 x 2.00mm (i.d.) column and UV detection was developed for the separation of hypericin, pseudohypericin and hyperforin. The development process involved a systematic investigation of buffer molarity, mobile phase composition, pH, flow rate, and temperature. This method was subsequently applied to assay selected commercially available St John's Wort products on the South African market. This system also provided the necessary accuracy, precision and reproducibility, as well as the advantages associated with the use of a narrow bore column as opposed to the use of the more commonly used wider bore columns. This method was validated and used to quantitate these three compounds in various commercial St John's Wort products. By applying this method to liquid chromatography – tandem mass spectrometry (LC-MS-MS), qualitative analyses of the same products was performed to obtain confirmation of the quantitative HPLC results. Mass spectrometry is a powerful detection tool that is more selective and specific than many detection systems used with HPLC. Natural medicines usually constitute a multitude of constituents with much potential interference. In this regard LC-MS-MS is a powerful tool, with its ability to unequivocally identify target analytes regardless of the presence of interferences or complex matrices. ESI-MS-MS was used for the qualitative analysis of the content of the naphthodianthrones and hyperforin in the respective tablet products assayed with HPLC. LC-MS-MS analyses were performed in order to identify the constituents and to verify the specificity of the HPLC method. High inter-product and inter-batch variability was observed for all nine compounds assayed. These quantitative results were confirmed with the respective qualitative analyses. This study confirms the need for strict quality control of herbal medicinal products commercially available to consumers.
- Full Text:
- Date Issued: 2003
- Authors: Wild, Tracy Joy
- Date: 2003
- Subjects: Hypericum perforatum , Hypericum perforatum -- Analysis , Hypericum perforatum -- Therapeutic use , Hypericum perforatum -- Physiological effect , Flavonoids -- Analysis
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:3804 , http://hdl.handle.net/10962/d1003282 , Hypericum perforatum , Hypericum perforatum -- Analysis , Hypericum perforatum -- Therapeutic use , Hypericum perforatum -- Physiological effect , Flavonoids -- Analysis
- Description: Most complementary medicines contain a multitude of chemical components, some of which are claimed to contribute to the biological activity of such products. Use of complementary medicines for preventative and therapeutic purposes is increasing rapidly worldwide. Unfortunately, although control of these products is essential to ensure quality, safety, and efficacy, the quality control of most herbal preparations is currently poor to non-existent, with little or no safety and efficacy data required to support the marketing and use of these products. The objective of this study was therefore to develop suitable analytical methods to qualitatively and quantitatively analyse the relevant components (rutin, isoquercitrin, hyperoside, quercitrin, quercetin, kaempferol, hypericin, pseudohypericin and hyperforin) in St John's Wort dosage forms for quality control purposes. A gradient HPLC method using a Luna 5·mC₁₈(2) 150 x 2.00mm internal diameter (i.d.) column and UV detection, was developed for the separation of six of the relevant flavonoid compounds in St John's Wort, namely rutin, isoquercitrin, hyperoside, quercitrin, quercetin and kaempferol. The development process involved a systematic investigation of gradient conditions, flow rate, and temperature. This method was subsequently applied to assay selected commercially available St John's Wort products. This system provided the necessary accuracy, precision and reproducibility and was associated with several advantages when compared to using standard bore (4.60 mm i.d.) HPLC columns. The method developed is currently the only known method that separates all six relevant flavonoids in a reasonable run time (less than 20 minutes). It is also one of the few methods that has sufficient separation between rutin, isoquercitrin and hyperoside. A qualitative method for the fingerprinting of flavonoid components was also developed, using capillary electrophoresis (CE). CE is a rapidly growing powerful analytical technique for the separation of charged compounds. Micellar electrokinetic chromatography (MEKC) is a very powerful electrophoretic technique that is capable of selectively resolving both neutral and ionic solutes in a single run. A MEKC method suitable for the separation and determination of various flavonoid constituents used as marker compounds in Hypericum perforatum was developed. Investigations into the effect of pH, ionic strength, applied voltage and capillary dimensions on separation were performed. The optimised method was then applied to qualitatively analyse various St John's Wort products on the market. This method was found to be advantageous in that it was simple, cost-effective, required minimal sample preparation and utilised very small quantities of sample. Due to the vast differences in chemical properties between the various marker and active components in St John's Wort, it was necessary to develop separate analytical methods for the flavonoids and for the other three relevant compounds (hypericin, pseudohypericin and hyperforin). An isocratic HPLC method using a Luna 5·mC₁₈(2) 150 x 2.00mm (i.d.) column and UV detection was developed for the separation of hypericin, pseudohypericin and hyperforin. The development process involved a systematic investigation of buffer molarity, mobile phase composition, pH, flow rate, and temperature. This method was subsequently applied to assay selected commercially available St John's Wort products on the South African market. This system also provided the necessary accuracy, precision and reproducibility, as well as the advantages associated with the use of a narrow bore column as opposed to the use of the more commonly used wider bore columns. This method was validated and used to quantitate these three compounds in various commercial St John's Wort products. By applying this method to liquid chromatography – tandem mass spectrometry (LC-MS-MS), qualitative analyses of the same products was performed to obtain confirmation of the quantitative HPLC results. Mass spectrometry is a powerful detection tool that is more selective and specific than many detection systems used with HPLC. Natural medicines usually constitute a multitude of constituents with much potential interference. In this regard LC-MS-MS is a powerful tool, with its ability to unequivocally identify target analytes regardless of the presence of interferences or complex matrices. ESI-MS-MS was used for the qualitative analysis of the content of the naphthodianthrones and hyperforin in the respective tablet products assayed with HPLC. LC-MS-MS analyses were performed in order to identify the constituents and to verify the specificity of the HPLC method. High inter-product and inter-batch variability was observed for all nine compounds assayed. These quantitative results were confirmed with the respective qualitative analyses. This study confirms the need for strict quality control of herbal medicinal products commercially available to consumers.
- Full Text:
- Date Issued: 2003
Pharmaceutical Pictograms: Part 1: Communicating Medicine Information to the Low-literate Patient
- Dowse, Roslind, Ehlers, Martina S
- Authors: Dowse, Roslind , Ehlers, Martina S
- Date: 2003
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/157026 , vital:40080
- Description: To assess the influence of formal education on the interpretation of pharmaceutical pictograms.
- Full Text:
- Date Issued: 2003
- Authors: Dowse, Roslind , Ehlers, Martina S
- Date: 2003
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/157026 , vital:40080
- Description: To assess the influence of formal education on the interpretation of pharmaceutical pictograms.
- Full Text:
- Date Issued: 2003
Pharmaceutical Pictograms: part 2: weird and wonderful interpretations
- Dowse, Roslind, Ehlers, Martina S
- Authors: Dowse, Roslind , Ehlers, Martina S
- Date: 2003
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/157037 , vital:40081
- Description: To assess the influence of formal education on the interpretation of pharmaceutical pictograms.
- Full Text:
- Date Issued: 2003
- Authors: Dowse, Roslind , Ehlers, Martina S
- Date: 2003
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/157037 , vital:40081
- Description: To assess the influence of formal education on the interpretation of pharmaceutical pictograms.
- Full Text:
- Date Issued: 2003
Photochemical studies of binuclear phenoxysubstituted phthalocyanines containing catecholate bridges
- Seotsanyana-Mokhosi, Itumeleng, Maree, Suzanne, Maree, M David, Nyokong, Tebello
- Authors: Seotsanyana-Mokhosi, Itumeleng , Maree, Suzanne , Maree, M David , Nyokong, Tebello
- Date: 2003
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/304808 , vital:58492 , xlink:href="https://doi.org/10.1142/S1088424603000239"
- Description: Binuclear ZnPc complexes covalently bridged by catechol units have been synthesized and their absorption and photochemical properties examined. The complexes studied are 1,2-bis-2',9',16',23'-triphenoxyphthalocyaninatozinc benzene (6a), 1,2-bis-2'-9',16',23'-tri-4-carboxyphe-noxyphthalocyaninatozinc benzene (6b), 1,2-bis-2',9',16',23'-tri-4-nitrophenoxyphthalocyaninato- zinc benzene (6c) and 1,2-bis-2'-9',16',23'-tri-4-tert-butylphenoxyphthalocyaninatozinc benzene (6d). Larger intramolecular coupling was observed for 6b and 6c, containing the carboxyphenoxy and nitrophenoxy substituents, respectively, than for 6a and 6d. A single Q band peak was observed for the fluorescence spectra of 6b and 6c, whereas, 6a and 6d showed a split Q band. The absence of the high energy fluorescence peaks corresponding to absorbance peaks in the 640 nm region, suggests that the intramolecular coupling is broken by excitation for complexes 6b and 6c.
- Full Text:
- Date Issued: 2003
Photochemical studies of binuclear phenoxysubstituted phthalocyanines containing catecholate bridges
- Authors: Seotsanyana-Mokhosi, Itumeleng , Maree, Suzanne , Maree, M David , Nyokong, Tebello
- Date: 2003
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/304808 , vital:58492 , xlink:href="https://doi.org/10.1142/S1088424603000239"
- Description: Binuclear ZnPc complexes covalently bridged by catechol units have been synthesized and their absorption and photochemical properties examined. The complexes studied are 1,2-bis-2',9',16',23'-triphenoxyphthalocyaninatozinc benzene (6a), 1,2-bis-2'-9',16',23'-tri-4-carboxyphe-noxyphthalocyaninatozinc benzene (6b), 1,2-bis-2',9',16',23'-tri-4-nitrophenoxyphthalocyaninato- zinc benzene (6c) and 1,2-bis-2'-9',16',23'-tri-4-tert-butylphenoxyphthalocyaninatozinc benzene (6d). Larger intramolecular coupling was observed for 6b and 6c, containing the carboxyphenoxy and nitrophenoxy substituents, respectively, than for 6a and 6d. A single Q band peak was observed for the fluorescence spectra of 6b and 6c, whereas, 6a and 6d showed a split Q band. The absence of the high energy fluorescence peaks corresponding to absorbance peaks in the 640 nm region, suggests that the intramolecular coupling is broken by excitation for complexes 6b and 6c.
- Full Text:
- Date Issued: 2003
Phthalocyanines and related complexes as electrocatalysts for the detection of nitric oxide
- Nyokong, Tebello, Vilakazi, Sibulelo
- Authors: Nyokong, Tebello , Vilakazi, Sibulelo
- Date: 2003
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/290346 , vital:56741 , xlink:href="https://doi.org/10.1016/S0039-9140(03)00356-4"
- Description: Metallophthalocyanine (MPc) and metalloporphyrin complexes as well as some metalloproteins including myoglobin, hemoglobin, cyanocobalamin and cytochrome c catalyse the detection of nitric oxide (NO). The catalytic process often involve changes in the oxidation state of the catalyst. These complexes catalyse both the reduction and oxidation of NO. MPc complexes containing electroactive central metals such as CoPc and FePc generally show better catalytic activity towards the detection of NO than complexes containing electroinacive central metals. However, the involvement of ring based redox processes was confirmed for the homogenous NO catalysis using CoPc.
- Full Text:
- Date Issued: 2003
- Authors: Nyokong, Tebello , Vilakazi, Sibulelo
- Date: 2003
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/290346 , vital:56741 , xlink:href="https://doi.org/10.1016/S0039-9140(03)00356-4"
- Description: Metallophthalocyanine (MPc) and metalloporphyrin complexes as well as some metalloproteins including myoglobin, hemoglobin, cyanocobalamin and cytochrome c catalyse the detection of nitric oxide (NO). The catalytic process often involve changes in the oxidation state of the catalyst. These complexes catalyse both the reduction and oxidation of NO. MPc complexes containing electroactive central metals such as CoPc and FePc generally show better catalytic activity towards the detection of NO than complexes containing electroinacive central metals. However, the involvement of ring based redox processes was confirmed for the homogenous NO catalysis using CoPc.
- Full Text:
- Date Issued: 2003
Phylogenetics of advanced snakes (Caenophidia) based on four mitochondrial genes
- Kelly, Christopher M R, Barker, Nigel P, Villet, Martin H
- Authors: Kelly, Christopher M R , Barker, Nigel P , Villet, Martin H
- Date: 2003
- Language: English
- Type: Article
- Identifier: vital:6960 , http://hdl.handle.net/10962/d1012005
- Description: Phylogenetic relationships among advanced snakes ( Acrochordus + Colubroidea = Caenophidia) and the position of the genus Acrochordus relative to colubroid taxa are contentious. These concerns were investigated by phylogenetic analysis of fragments from four mitochondrial genes representing 62 caenophidian genera and 5 noncaenophidian taxa. Four methods of phylogeny reconstruction were applied: matrix representation with parsimony (MRP) supertree consensus, maximum parsimony, maximum likelihood, and Bayesian analysis. Because of incomplete sampling, extensive missing data were inherent in this study. Analyses of individual genes retrieved roughly the same clades, but branching order varied greatly between gene trees, and nodal support was poor. Trees generated from combined data sets using maximum parsimony, maximum likelihood, and Bayesian analysis had medium to low nodal support but were largely congruent with each other and with MRP supertrees. Conclusions about caenophidian relationships were based on these combined analyses. The Xenoderminae, Viperidae, Pareatinae, Psammophiinae, Pseudoxyrophiinae, Homalopsinae, Natricinae, Xenodontinae, and Colubrinae (redefined) emerged as monophyletic, whereas Lamprophiinae, Atractaspididae, and Elapidae were not in one or more topologies. A clade comprising Acrochordus and Xenoderminae branched closest to the root, and when Acrochordus was assessed in relation to a colubroid subsample and all five noncaenophidians, it remained associated with the Colubroidea. Thus, Acrochordus + Xenoderminae appears to be the sister group to the Colubroidea, and Xenoderminae should be excluded from Colubroidea. Within Colubroidea, Viperidae was the most basal clade. Other relationships appearing in all final topologies were (1) a clade comprising Psammophiinae, Lamprophiinae, Atractaspididae, Pseudoxyrophiinae, and Elapidae, within which the latter four taxa formed a subclade, and (2) a clade comprising Colubrinae, Natricinae, and Xenodontinae, within which the latter two taxa formed a subclade. Pareatinae and Homalopsinae were the most unstable clades.
- Full Text:
- Date Issued: 2003
- Authors: Kelly, Christopher M R , Barker, Nigel P , Villet, Martin H
- Date: 2003
- Language: English
- Type: Article
- Identifier: vital:6960 , http://hdl.handle.net/10962/d1012005
- Description: Phylogenetic relationships among advanced snakes ( Acrochordus + Colubroidea = Caenophidia) and the position of the genus Acrochordus relative to colubroid taxa are contentious. These concerns were investigated by phylogenetic analysis of fragments from four mitochondrial genes representing 62 caenophidian genera and 5 noncaenophidian taxa. Four methods of phylogeny reconstruction were applied: matrix representation with parsimony (MRP) supertree consensus, maximum parsimony, maximum likelihood, and Bayesian analysis. Because of incomplete sampling, extensive missing data were inherent in this study. Analyses of individual genes retrieved roughly the same clades, but branching order varied greatly between gene trees, and nodal support was poor. Trees generated from combined data sets using maximum parsimony, maximum likelihood, and Bayesian analysis had medium to low nodal support but were largely congruent with each other and with MRP supertrees. Conclusions about caenophidian relationships were based on these combined analyses. The Xenoderminae, Viperidae, Pareatinae, Psammophiinae, Pseudoxyrophiinae, Homalopsinae, Natricinae, Xenodontinae, and Colubrinae (redefined) emerged as monophyletic, whereas Lamprophiinae, Atractaspididae, and Elapidae were not in one or more topologies. A clade comprising Acrochordus and Xenoderminae branched closest to the root, and when Acrochordus was assessed in relation to a colubroid subsample and all five noncaenophidians, it remained associated with the Colubroidea. Thus, Acrochordus + Xenoderminae appears to be the sister group to the Colubroidea, and Xenoderminae should be excluded from Colubroidea. Within Colubroidea, Viperidae was the most basal clade. Other relationships appearing in all final topologies were (1) a clade comprising Psammophiinae, Lamprophiinae, Atractaspididae, Pseudoxyrophiinae, and Elapidae, within which the latter four taxa formed a subclade, and (2) a clade comprising Colubrinae, Natricinae, and Xenodontinae, within which the latter two taxa formed a subclade. Pareatinae and Homalopsinae were the most unstable clades.
- Full Text:
- Date Issued: 2003
Physiological, perceptual and performance responses during cricket activity
- Authors: King, Gregory Allen
- Date: 2003
- Subjects: Cricket , Sports -- Psychological aspects , Sports -- Physiological aspects
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5131 , http://hdl.handle.net/10962/d1005210 , Cricket , Sports -- Psychological aspects , Sports -- Physiological aspects
- Description: The present study sought to determine the influence of environmental conditions and protective clothing on physiological, perceptual and performance responses during batting activity. The investigation examined mean skin temperature, average heart rate, estimated sweat rate, rating of perceived exertion, thermal sensation rating, average sprint time and pre-post choice reaction time. Twenty-five cricketers (18-22 yr, 73.1 ± 9.6 kg, 1768 ± 75 mm, 12.6 ± 3.1% body fat, 1.89 ± 0.16 m2) performed a work-bout consisting of a seven-Over batting period, during which time they faced deliveries from a bowling machine and performed two shuttle runs every third ball to total four sprints per Over. Trials were carried out under High-stress (23.8 ± 2.2 °C) and Low-stress (13.3 ± 1.9 °C) environmental conditions (WBGT). Within each environmental condition subjects performed the test wearing full protective batting gear and no protective gear. Thus, four specific conditions were examined; high full-gear (HFG), high no-gear (HNG), low full-gear (LFG) and low no-gear (LNG). Two-way ANOVAs were calculated to determine whether there were differences between environmental conditions and whether differences existed between the clothing conditions. One-way ANOVAs were utilised to compute differences between the four specific conditions combining clothing and environment. High environmental stress and wearing protective clothing caused batsmen to experience significant physiological strain. The environment was the greatest stressor, with the protective gear exacerbating these effects. However, when padding covered skin areas directly, this was the primary skin temperature stressor, particularly later in the activity. For skin temperature and heart rate, the strain was the most pronounced at the end of the trials. Perceptual responses indicated that the protective gear had no influence on effort sense, thermal sensation or thermal comfort. However, environmental conditions had an effect, and High-stress conditions resulted in significantly higher perceptions of effort, elevated sensations of heat and greater thermal discomfort. Effort was perceived to be greatest towards the end of the trial. There were mixed findings for performance factors. In general sprint performance was not hindered by environmental stress, but protective clothing caused a reduction in several sprint times. Choice reaction times were for the most part unaffected by either environment or clothing and few differences were observed between pre and post times. It is contended that intense short duration batting activity, likely encountered during one-day participation, imposes a stress on batsmen. The stress is greater when conditions are warmer and protective padding is worn, although it is not sufficient to impede choice reaction time. However, protective gear did have a deleterious effect on sprint performance.
- Full Text:
- Date Issued: 2003
- Authors: King, Gregory Allen
- Date: 2003
- Subjects: Cricket , Sports -- Psychological aspects , Sports -- Physiological aspects
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5131 , http://hdl.handle.net/10962/d1005210 , Cricket , Sports -- Psychological aspects , Sports -- Physiological aspects
- Description: The present study sought to determine the influence of environmental conditions and protective clothing on physiological, perceptual and performance responses during batting activity. The investigation examined mean skin temperature, average heart rate, estimated sweat rate, rating of perceived exertion, thermal sensation rating, average sprint time and pre-post choice reaction time. Twenty-five cricketers (18-22 yr, 73.1 ± 9.6 kg, 1768 ± 75 mm, 12.6 ± 3.1% body fat, 1.89 ± 0.16 m2) performed a work-bout consisting of a seven-Over batting period, during which time they faced deliveries from a bowling machine and performed two shuttle runs every third ball to total four sprints per Over. Trials were carried out under High-stress (23.8 ± 2.2 °C) and Low-stress (13.3 ± 1.9 °C) environmental conditions (WBGT). Within each environmental condition subjects performed the test wearing full protective batting gear and no protective gear. Thus, four specific conditions were examined; high full-gear (HFG), high no-gear (HNG), low full-gear (LFG) and low no-gear (LNG). Two-way ANOVAs were calculated to determine whether there were differences between environmental conditions and whether differences existed between the clothing conditions. One-way ANOVAs were utilised to compute differences between the four specific conditions combining clothing and environment. High environmental stress and wearing protective clothing caused batsmen to experience significant physiological strain. The environment was the greatest stressor, with the protective gear exacerbating these effects. However, when padding covered skin areas directly, this was the primary skin temperature stressor, particularly later in the activity. For skin temperature and heart rate, the strain was the most pronounced at the end of the trials. Perceptual responses indicated that the protective gear had no influence on effort sense, thermal sensation or thermal comfort. However, environmental conditions had an effect, and High-stress conditions resulted in significantly higher perceptions of effort, elevated sensations of heat and greater thermal discomfort. Effort was perceived to be greatest towards the end of the trial. There were mixed findings for performance factors. In general sprint performance was not hindered by environmental stress, but protective clothing caused a reduction in several sprint times. Choice reaction times were for the most part unaffected by either environment or clothing and few differences were observed between pre and post times. It is contended that intense short duration batting activity, likely encountered during one-day participation, imposes a stress on batsmen. The stress is greater when conditions are warmer and protective padding is worn, although it is not sufficient to impede choice reaction time. However, protective gear did have a deleterious effect on sprint performance.
- Full Text:
- Date Issued: 2003
Pipes, poles and people:
- Authors: Kyazze, Sim
- Date: 2003
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/159153 , vital:40273 , https://hdl.handle.net/10520/EJC146268
- Description: Tina James, a South African ICT consultant, tells the story of Minnie Barendse Kruger who had been struggling to get a Khoisan Cultural Village going in the Eastern Cape. Kruger set up a restaurant where traditional food is prepared, and the Barendse Griquas Trust stepped in and helped set up a multi-purpose Community Centre.
- Full Text:
- Date Issued: 2003
- Authors: Kyazze, Sim
- Date: 2003
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/159153 , vital:40273 , https://hdl.handle.net/10520/EJC146268
- Description: Tina James, a South African ICT consultant, tells the story of Minnie Barendse Kruger who had been struggling to get a Khoisan Cultural Village going in the Eastern Cape. Kruger set up a restaurant where traditional food is prepared, and the Barendse Griquas Trust stepped in and helped set up a multi-purpose Community Centre.
- Full Text:
- Date Issued: 2003
Politics of asylum : sovereign considerations in the multilateral and humanitarian practices of refugee protection in post-apartheid South Africa
- Authors: Oduba, Victor
- Date: 2003
- Subjects: Refugees -- Africa , Refugees -- Government policy -- South Africa , Refugees -- Legal status, laws, etc. -- South Africa , Asylum, Right of -- South Africa
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2870 , http://hdl.handle.net/10962/d1007725 , Refugees -- Africa , Refugees -- Government policy -- South Africa , Refugees -- Legal status, laws, etc. -- South Africa , Asylum, Right of -- South Africa
- Description: Most scholars claim that international human rights norms embodied in formal international declarations and treaties have an important impact on domestic political interests and governmental practices. This reasoning about the impact of global human rights is often applied to the post-apartheid South African immigration and refugee policies. While I acknowledge that the ratification of United Nations Conventions on refugees has altered the traditional sovereignty considerations of South Africa towards asylum seekers, I take issue with the claims that South African refugee and asylum policies are primarily motivated and based on humanitarian considerations. Instead, I argue that these policies are based on sovereign considerations and strategic foreign policy interests. As a result this sovereign interests of South Africa to study has sought to demonstrate that largely explain decisions on the part accept or reject refugees. Although norms diffusion, international advocacy networks, and prestige factors have made a big impact, in practice the refugee policy has continued to reflect South Africa's strategic interests and domestic considerations at all levels. However, I have not argued that South Africa should overlook its national and foreign interests and abide by international human rights norms regardless of the cost of doing so. I have only sought to demonstrate that refugee protection is more when powerful national interests find it conducive to manage the destabilizing refugee flows.
- Full Text:
- Date Issued: 2003
- Authors: Oduba, Victor
- Date: 2003
- Subjects: Refugees -- Africa , Refugees -- Government policy -- South Africa , Refugees -- Legal status, laws, etc. -- South Africa , Asylum, Right of -- South Africa
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2870 , http://hdl.handle.net/10962/d1007725 , Refugees -- Africa , Refugees -- Government policy -- South Africa , Refugees -- Legal status, laws, etc. -- South Africa , Asylum, Right of -- South Africa
- Description: Most scholars claim that international human rights norms embodied in formal international declarations and treaties have an important impact on domestic political interests and governmental practices. This reasoning about the impact of global human rights is often applied to the post-apartheid South African immigration and refugee policies. While I acknowledge that the ratification of United Nations Conventions on refugees has altered the traditional sovereignty considerations of South Africa towards asylum seekers, I take issue with the claims that South African refugee and asylum policies are primarily motivated and based on humanitarian considerations. Instead, I argue that these policies are based on sovereign considerations and strategic foreign policy interests. As a result this sovereign interests of South Africa to study has sought to demonstrate that largely explain decisions on the part accept or reject refugees. Although norms diffusion, international advocacy networks, and prestige factors have made a big impact, in practice the refugee policy has continued to reflect South Africa's strategic interests and domestic considerations at all levels. However, I have not argued that South Africa should overlook its national and foreign interests and abide by international human rights norms regardless of the cost of doing so. I have only sought to demonstrate that refugee protection is more when powerful national interests find it conducive to manage the destabilizing refugee flows.
- Full Text:
- Date Issued: 2003
Pollination success in a deceptive orchid is enhanced by co-occurring rewarding magnet plants
- Johnson, Steven D, Peter, Craig I, Nilsson, L Anders, Agren, Jon
- Authors: Johnson, Steven D , Peter, Craig I , Nilsson, L Anders , Agren, Jon
- Date: 2003
- Language: English
- Type: Article
- Identifier: vital:6520 , http://hdl.handle.net/10962/d1005949 , http://www.jstor.org/stable/3449962
- Description: It has been debated whether pollination success in nonrewarding plants that flower in association with nectar-producing plants will be diminished by competition for pollinator visits or, alternatively, enhanced through increased local abundance of pollinators (the magnet species effect). We experimentally evaluated these effects using the nonrewarding bumblebee-pollinated orchid Anacamptis morio and associated nectar-producing plants at a site in Sweden. Pollination success (estimated as pollen receipt and pollen removal) in A. morio was significantly greater for individuals translocated to patches of nectar-producing plants (Geum rivale and Allium schoenoprasum) than for individuals placed outside (similar to20 m away) such patches. These results provide support for the existence of a facilitative magnet species effect in the interaction between certain nectar plants and A. morio. To determine the spatial scale of these interactions, we correlated the visitation rate to flowers of A. morio with the density of sympatric nectar plants in 1-m(2) and 100-m(2) plots centered around groups of translocated plants, and at the level of whole meadows (similar to0.5-2 ha). Visitation rate to flowers of A. morio was not correlated with the 1-m(2) patch density of G. rivale and A. schoenoprasum, but showed a significant positive relationship with density of these nectar plants in 100-m(2) plots. In addition, visitation to flowers of A. morio was strongly and positively related to the density of A. schoenoprasum at the level of the meadow. Choice experiments showed that bees foraging on the purple flowers of A. schoenoprasum (a particularly effective magnet species) visit the purple flowers of A. morio more readily (47.6% of choices) than bees foraging on the yellow flowers of Lotus corniculatus (17% of choices). Overall similarity in flower color and shape may increase the probability that a pollinator will temporarily shift from a nectar-producing "magnet" plant to a nonrewarding plant. We discuss the possibility of a mimicry continuum between those orchids that exploit instinctive food-seeking behavior of pollinators and those that show an adaptive resemblance to nectar-producing plants.
- Full Text:
- Date Issued: 2003
- Authors: Johnson, Steven D , Peter, Craig I , Nilsson, L Anders , Agren, Jon
- Date: 2003
- Language: English
- Type: Article
- Identifier: vital:6520 , http://hdl.handle.net/10962/d1005949 , http://www.jstor.org/stable/3449962
- Description: It has been debated whether pollination success in nonrewarding plants that flower in association with nectar-producing plants will be diminished by competition for pollinator visits or, alternatively, enhanced through increased local abundance of pollinators (the magnet species effect). We experimentally evaluated these effects using the nonrewarding bumblebee-pollinated orchid Anacamptis morio and associated nectar-producing plants at a site in Sweden. Pollination success (estimated as pollen receipt and pollen removal) in A. morio was significantly greater for individuals translocated to patches of nectar-producing plants (Geum rivale and Allium schoenoprasum) than for individuals placed outside (similar to20 m away) such patches. These results provide support for the existence of a facilitative magnet species effect in the interaction between certain nectar plants and A. morio. To determine the spatial scale of these interactions, we correlated the visitation rate to flowers of A. morio with the density of sympatric nectar plants in 1-m(2) and 100-m(2) plots centered around groups of translocated plants, and at the level of whole meadows (similar to0.5-2 ha). Visitation rate to flowers of A. morio was not correlated with the 1-m(2) patch density of G. rivale and A. schoenoprasum, but showed a significant positive relationship with density of these nectar plants in 100-m(2) plots. In addition, visitation to flowers of A. morio was strongly and positively related to the density of A. schoenoprasum at the level of the meadow. Choice experiments showed that bees foraging on the purple flowers of A. schoenoprasum (a particularly effective magnet species) visit the purple flowers of A. morio more readily (47.6% of choices) than bees foraging on the yellow flowers of Lotus corniculatus (17% of choices). Overall similarity in flower color and shape may increase the probability that a pollinator will temporarily shift from a nectar-producing "magnet" plant to a nonrewarding plant. We discuss the possibility of a mimicry continuum between those orchids that exploit instinctive food-seeking behavior of pollinators and those that show an adaptive resemblance to nectar-producing plants.
- Full Text:
- Date Issued: 2003
Population biology of Octopus vulgaris on the temperate south-eastern coast of South Africa
- Oosthuizen, A, Smale, Malcolm J
- Authors: Oosthuizen, A , Smale, Malcolm J
- Date: 2003
- Language: English
- Type: Article
- Identifier: vital:6768 , http://hdl.handle.net/10962/d1008045
- Description: Population structure and biology of Octopus vulgaris was investigated along the south-eastern coast of South Africa. Samples were collected inter- and sub-tidally as a precursor to the establishment of an experimental octopus fishery in the region. In total, 300 (intertidal) and 147 (subtidal) O. vulgaris were collected over a two year period. Females were found to dominate the intertidal area (sex ratio 2:1), while no difference was found subtidally (sex ratio 1:1). Of those collected intertidally, immature females were most prevalent while males ranged from immature to mature. Mature females were only found subtidally. A marked size difference was apparent, with the subtidal octopus being substantially larger. Although brooding females were found throughout the year, numbers peaked in summer. Individual fecundity ranged between 42,000–790,000 eggs. The total number of eggs produced and the number of eggs per egg string were correlated to female size. Diet did not vary greatly between the inter- and sub-tidal areas, with the main prey items being crustaceans, teleosts and octopus. It appears that the immature females use the intertidal area to feed and grow, before migrating to deeper areas to mature and spawn.
- Full Text:
- Date Issued: 2003
- Authors: Oosthuizen, A , Smale, Malcolm J
- Date: 2003
- Language: English
- Type: Article
- Identifier: vital:6768 , http://hdl.handle.net/10962/d1008045
- Description: Population structure and biology of Octopus vulgaris was investigated along the south-eastern coast of South Africa. Samples were collected inter- and sub-tidally as a precursor to the establishment of an experimental octopus fishery in the region. In total, 300 (intertidal) and 147 (subtidal) O. vulgaris were collected over a two year period. Females were found to dominate the intertidal area (sex ratio 2:1), while no difference was found subtidally (sex ratio 1:1). Of those collected intertidally, immature females were most prevalent while males ranged from immature to mature. Mature females were only found subtidally. A marked size difference was apparent, with the subtidal octopus being substantially larger. Although brooding females were found throughout the year, numbers peaked in summer. Individual fecundity ranged between 42,000–790,000 eggs. The total number of eggs produced and the number of eggs per egg string were correlated to female size. Diet did not vary greatly between the inter- and sub-tidal areas, with the main prey items being crustaceans, teleosts and octopus. It appears that the immature females use the intertidal area to feed and grow, before migrating to deeper areas to mature and spawn.
- Full Text:
- Date Issued: 2003
Potter's fingerprints: some prehistoric southern African utilityware in an intimate light.
- Authors: Steele, John
- Date: 2003
- Language: English
- Type: text , Article
- Identifier: http://hdl.handle.net/11260/945 , vital:30070
- Description: Extensive archaeological excavations in southern Africa during the past century have revealed a richly described heritage of widely distributed First-Millennium (C.E.) Agriculturist ceramics. In viewing both artefacts and assessments thereof it can be observed that ways of thinking shape ways of seeing, and explanations ofwhat is seen. Thus, because conceptual frameworks are inseparable from what is observed and explanations that result, consideration is given to some particular mindsets that have led to recent theories concenring local prehistoric material culture. In conclusion, a brief look at dialogues initiated by some contemporary potters who interrogate cherished lifeways and belief systems serve to elucidate current trends towards finding meaning in prehistoric southern African ceramics.
- Full Text:
- Date Issued: 2003
- Authors: Steele, John
- Date: 2003
- Language: English
- Type: text , Article
- Identifier: http://hdl.handle.net/11260/945 , vital:30070
- Description: Extensive archaeological excavations in southern Africa during the past century have revealed a richly described heritage of widely distributed First-Millennium (C.E.) Agriculturist ceramics. In viewing both artefacts and assessments thereof it can be observed that ways of thinking shape ways of seeing, and explanations ofwhat is seen. Thus, because conceptual frameworks are inseparable from what is observed and explanations that result, consideration is given to some particular mindsets that have led to recent theories concenring local prehistoric material culture. In conclusion, a brief look at dialogues initiated by some contemporary potters who interrogate cherished lifeways and belief systems serve to elucidate current trends towards finding meaning in prehistoric southern African ceramics.
- Full Text:
- Date Issued: 2003