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Multivariate morphometric analysis and behaviour of honeybees (Apis Mellifera L.) in the southern regions of Ethiopia

  • Authors: Amssalu, Argaw Bezabeh
  • Date: 2003
  • Subjects: Honeybee -- Ethiopia -- Behavior Honeybee -- Ethiopia
  • Language: English
  • Type: Thesis , Doctoral , PhD
  • Identifier: vital:5616 , http://hdl.handle.net/10962/d1003130
  • Description: Morphometric and behavioural characteristics of honeybees, Apis mellifera were analysed using multivariate and bivariate statistical methods to characterise honeybees of southern Ethiopian region. A total of 33800 morphometric character measurements were taken from 2600 individual worker honeybees of 130 honeybee colonies collected at 26 sampling localities with an average inter-locality distance of 89km to determine the occurrence of morphoclusters. 117 experienced farmer beekeepers and beekeeping experts were interviewed on pre-tested questionnaire to investigate the behavioural characteristics of these honeybees in their respective areas. Morphometric characters associated with pigmentation and body size exhibited a higher discriminant power while forewing venation angles (B4, N23 and 026) lack discriminatory power to segregate honeybees in the southern Ethiopian region. Principal components and discriminant analyses using the most discriminatory morphological characters delineated four statistically distinct morphoclusters in the southern Ethiopian region: the smallest and yellow honeybees, A. m. woyi-gambella which are different from all African honeybees, occur in the western and southern lowlands; the small and yellowiest honeybees, Apis mellifera jemenitica in the eastern escarpment; the largest and darkest honeybees, Apis mellifera bandasii in the central and eastern highlands; and dark honeybees, Apis mellifera scutellata in the wet tropical forests. High intracolonial and intercolonial variances within and between the boundaries of the honeybee groups were detected. The former suggests areas of ecological instability, while the latter areas of transitional or natural hybridisation zones. These areas are characterised by transitional ecological zones having intermediate climate and physiography. Even though honeybees of the southern Ethiopian region are generally dark and small, they show a high tendency to reproductive swarming, migration and aggressiveness, great variation in pigmentation, size and behaviour were observed both within and between the groups. A. m. jemenitica honeybees have a high propensity to migration and less a tendency for reproductive swarming. A. m. bandasii and A. m. scutellata have a high inclination to reproductive swarming and the former has a lesser and the later intermediate propensity to migration. A. m. woyi-gambella honeybees have intermediate swarming and migration tendencies. These results revealed that reproductive swarming and migration are higher in resource-rich and resource-poor areas respectively. Honey plants of the central highlands of Ethiopia are predominantly herbaceous in nature and mainly grow on open and cultivated lands. The bulk of pollen collected came comparatively from few genera. Strong correlation was observed between the intensities of flowering and rainfall. Reproductive swarming and migration occur during high and low intensity of flowering respectively.
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  • Date Issued: 2003

Mythic and theoretic aspects of the concept of 'the unconscious' in popular and psychological discourse

  • Authors: Edwards, David J A
  • Date: 2003
  • Language: English
  • Type: Article
  • Identifier: vital:6227 , http://hdl.handle.net/10962/d1007777
  • Description: From the introduction: In Greek mythology, Typhon was the youngest son of Gaea (the Earth) and Tartarus (the underworld). Typhon was not a beautiful baby. He was a grisly monster with a hundred dragons' heads. He was one of the Titans, a group of powerful and dangerous creatures who rebelled against Zeus, the King of the Gods. The rebellion was crushed and Typhon was imprisoned under Mount Etna, the volcano in Sicily which was active in classical times and remains active today. It was said that when Typhon raged, the earth shook and Etna erupted. Many such tales from mythology from all over world seem to dramatize aspects of our relationship with potent forces of which we have little understanding and over which we have little control. Many of these forces are less concrete than the forces of nature. They arise from our apprehension of our existential predicaments, our interpersonal vulnerability and the intensity of our own psychological pain. In many contemporary discourses this territory is referred to more neutrally as ‘the unconscious;’ but the unconscious will always elude our attempts to capture it in words.
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  • Date Issued: 2003

NeGPAIM : a model for the proactive detection of information security intrusions, utilizing fuzzy logic and neural network techniques

  • Authors: Botha, Martin
  • Date: 2003
  • Subjects: Computer security , Fuzzy logic , Neural networks (Computer science)
  • Language: English
  • Type: Thesis , Doctoral , DTech (Computer Studies)
  • Identifier: vital:10792 , http://hdl.handle.net/10948/142 , Computer security , Fuzzy logic , Neural networks (Computer science)
  • Description: “Information is the lifeblood of any organisation and everything an organisation does involves using information in some way” (Peppard, 1993, p.5). Therefore, it can be argued that information is an organisation’s most precious asset and as with all other assets, like equipment, money, personnel, and so on, this asset needs to be protected properly at all times (Whitman & Mattord, 2003, pp.1-14). The introduction of modern technologies, such as e-commerce, will not only increase the value of information, but will also increase security requirements of those organizations that are intending to utilize such technologies. Evidence of these requirements can be observed in the 2001 CSI/FBI Computer Crime and Security Survey (Power, 2001). According to this source, the annual financial losses caused through security breaches in 2001 have increased by 277% when compared to the results from 1997. The 2002 and 2003 Computer Crime and Security Survey confirms this by stating that the threat of computer crime and other related information security breaches continues unabated and that the financial toll is mounting (Richardson, 2003). Information is normally protected by means of a process of identifying, implementing, managing and maintaining a set of information security controls, countermeasures or safeguards (GMITS, 1998). In the rest of this thesis, the term security controls will be utilized when referring to information protection mechanisms or procedures. These security controls can be of a physical (for example, door locks), a technical (for example, passwords) and/or a procedural nature (for example, to make back-up copies of critical files)(Pfleeger, 2003, pp.22-23; Stallings, 1995, p.1). The effective identification, implementation, management and maintenance of this set of security controls are usually integrated into an Information Security Management Program, the objective of which is to ensure an acceptable level of information confidentiality, integrity and availability within the organisation at all times (Pfleeger, 2003, pp.10-12; Whitman & Mattord, 2003, pp.1-14; Von Solms, 1993). Once the most effective security controls have been identified and implemented, it is important that this level of security be maintained through a process of continued control. For this reason, it is important that proper change management, measurement, audit, monitoring and detection be implemented (Bruce & Dempsey, 1997). Monitoring and detection are important functions and refer to the ability to identify and detect situations where information security policies have been compromised and/or breached or security violations have taken place (BS 7799, 1999; GMITS, 1998; Von Solms, 1993). The Information Security Officer is usually the person responsible for most of the operational tasks in the control process within an Information Security Management Program (Von Solms, 1993). In practice, these tasks could also be performed by a system administrator, network administrator, etc. In the rest of the thesis the person responsible for these tasks will be referred to as system administrator. These tasks have proved to be very challenging and demanding. The main reason for this is the rapid advancement of technology in the discipline of Information Technology, for example, the modern distributed computing environment, the Internet, the “freedom” of end-users, the introduction of e-commerce, and etc. (Whitman & Mattord, 2003, p.9; Sundaram, 2000, p.1; Moses, 2001, p.6; Allen, 2001, p.1). As a result of the importance of this control process, and especially the monitoring and detection tasks, it is vital that the system administrator has proper tools at his/her disposal to perform this task effectively. Many of the tools that are currently available to the system administrator, utilize technical controls, such as, audit logs and user profiles. Audit logs are normally used to record all events executed on a system. These logs are simply files that record security and non-security related events that take place on a computer system within an organisation. For this reason, these logs can be used by these tools to gain valuable information on security violations, such as intrusions and, therefore, are able to monitor the current actions of each user (Microsoft, 2002; Smith, 1989, pp. 116-117). User profiles are files that contain information about users` desktop operating environments and are used by the operating system to structure each user environment so that it is the same each time a user logs onto the system (Microsoft, 2002; Block, 1994, p.54). Thus, a user profile is used to indicate which actions the user is allowed to perform on the system. Both technical controls (audit logs and user profiles) are frequently available in most computer environments (such as, UNIX, Firewalls, Windows, etc.) (Cooper et al, 1995, p.129). Therefore, seeing that the audit logs record most events taking place on an information system and the user profile indicates the authorized actions of each user, the system administrator could most probably utilise these controls in a more proactive manner.
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  • Date Issued: 2003

Non-payment of municipal rates and service charges with reference to the Nelson Mandela Metropolitan municipality

  • Authors: Ngxongo, Malusi
  • Date: 2003
  • Subjects: Collecting of accounts , Municipal default -- South Africa -- Port Elizabeth , Public utilities -- South Africa -- Port Elizabeth
  • Language: English
  • Type: Thesis , Masters , MTech (Public Management)
  • Identifier: vital:10772 , http://hdl.handle.net/10948/258 , Collecting of accounts , Municipal default -- South Africa -- Port Elizabeth , Public utilities -- South Africa -- Port Elizabeth
  • Description: The local government sphere is comprised of municipalities whose functions include the provision of consumer services. A substantial portion of municipal revenue, which is also used for service provision, is derived from rates and service charges. Through the billing process, the municipality stipulates the amount due to be paid by each account holder. In the case of rates and consumer tariffs, this usually occurs on a monthly basis. Towards the end of 2002, overdue rates and service charges in the Nelson Mandela Metropolitan Municipality amounted to over R800 million. In spite of various attempts undertaken by the municipality to collect overdue amounts, some residents are struggling to pay. Various reasons have been advanced for this scenario. However non-payment of rates and service charges has a negative impact on municipal budget and service delivery. Probably, if alternatives to the current credit control and revenue collection processes could be found, non-payment of rates and service charges could be eliminated.
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  • Date Issued: 2003

Novel approaches to the monitoring of computer networks

  • Authors: Halse, G A
  • Date: 2003
  • Subjects: Computer networks , Computer networks -- Management , Computer networks -- South Africa -- Grahamstown , Rhodes University -- Information Technology Division
  • Language: English
  • Type: Thesis , Masters , MSc
  • Identifier: vital:4645 , http://hdl.handle.net/10962/d1006601
  • Description: Traditional network monitoring techniques suffer from a number of limitations. They are usually designed to solve the most general case, and as a result often fall short of expectation. This project sets out to provide the network administrator with a set of alternative tools to solve specific, but common, problems. It uses the network at Rhodes University as a case study and addresses a number of issues that arise on this network. Four problematic areas are identified within this network: the automatic determination of network topology and layout, the tracking of network growth, the determination of the physical and logical locations of hosts on the network, and the need for intelligent fault reporting systems. These areas are chosen because other network monitoring techniques have failed to adequately address these problems, and because they present problems that are common across a large number of networks. Each area is examined separately and a solution is sought for each of the problems identified. As a result, a set of tools is developed to solve these problems using a number of novel network monitoring techniques. These tools are designed to be as portable as possible so as not to limit their use to the case study network. Their use within Rhodes, as well as their applicability to other situations is discussed. In all cases, any limitations and shortfalls in the approaches that were employed are examined.
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  • Date Issued: 2003

Nursing in transition: negotiating the experience: an exploration of the impact of the aids pandemic on the subjective work experiences of peri-urban nurses

  • Authors: Brown, Lisa Joy
  • Date: 2003
  • Subjects: AIDS (Disease) -- Nursing -- South Africa , AIDS (Disease) -- Nursing -- Psychological aspects , Nurses -- Job stress -- South Africa
  • Language: English
  • Type: Thesis , Masters , MA
  • Identifier: vital:3252 , http://hdl.handle.net/10962/d1015962
  • Description: A substantial amount of international research exists examining the impact of HIV/AIDS on health care workers. However, the impact of HIV/AIDS on nursing staff in South Africa has been relatively neglected. The primary objective of this study was to examine the impact of the AIDS pandemic on the subjective work experiences of peri-urban nurses in South Africa. The study explored the relationship between external changes in the nurses' working environment and their internal psychological responses for negotiating this change. A focus group of eight nurses was conducted, followed by indepth individual interviews with three group members. A grounded theory method was utilised to process and analyse the data. The research showed that nurses experience two forms of change. It was suggested that nurses respond to external changes in a manner designed to maximise their control and sense of meaning in an unpredictable environment. This accommodation involves the restoration of an internal psychological equilibrium through a process of balancing positive and negative experiences. The attainment of such an acceptable equilibrium may allow for diminished stress, increased satisfaction or fulfilment and the validation of personal and professional significance.
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  • Date Issued: 2003

Observed metabolic changes in male Wistar rats after treatment with an antidepressant implied in undesirable weight gain, or Sutherlandia frutescens for Type II diabetes

  • Authors: Chadwick, Wayne
  • Date: 2003
  • Subjects: Rats -- Metabolism , Non-insulin-dependent diabetes -- Research , Rats as laboratory animals
  • Language: English
  • Type: Thesis , Masters , MSc
  • Identifier: vital:11068 , http://hdl.handle.net/10948/313 , Rats -- Metabolism , Non-insulin-dependent diabetes -- Research , Rats as laboratory animals
  • Description: Type II diabetes is fast becoming a growing problem in developed countries worldwide. Traditionally the median age for diagnosis was around sixty, but recent surveys have shown that the entire age distribution curve has shifted to the left. Western countries boast the worst statistics in which type II diabetes is being reported in children under the age of ten. At such a young age the disease often goes undiagnosed for long periods of time allowing considerable damage to occur. The incidence of type II diabetes is thought to be parallel with the growing rate of obesity associated with a characteristically unhealthy western diet. Type II diabetes is an extremely expensive disease to manage, and with the rapid growth of this pandemic our country will soon feel the economic burden of this disease. It is for this reason that cheaper medication needs to be investigated in the form of traditional plants, such as Sutherlandia frutescens. Prescription medication, such as tricyclic antidepressants, may also increase body weight or appetite thereby playing a role in obesity. The cause of weight gain in such cases may go unrecognized or lead to cessation of the medication with or without the practitioner’s knowledge or approval. It is therefore necessary to investigate the causative agents responsible for the excessive weight gain. Drinking water containing extracts of the S. frutescens, metformin (a well known type II diabetes medication) and amitriptyline (a common tricyclic antidepressant) was administered to three groups of ten male Wistar rats. The control group received water without any medication. The rat’s weight and food consumption was monitored throughout the trial and their oxygen consumption was also determined. Rats were sacrificed after four months of medicinal compliance and glucose uptake, in the presence and absence of insulin, was tested in epididymal fat, liver and muscle. Fasting plasma glucose levels, lipoprotein, cholesterol and triglyceride concentrations were also determined.
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  • Date Issued: 2003

Occupational medical examinations and labour law

  • Authors: Lapere, Jan Noel Romain
  • Date: 2003
  • Subjects: Employees -- Medical examinations -- South Africa , Labor laws and legislation -- South Africa , Medical screening -- South Africa , Industrial hygiene -- South Africa
  • Language: English
  • Type: Thesis , Masters , LLM
  • Identifier: vital:11045 , http://hdl.handle.net/10948/302 , Employees -- Medical examinations -- South Africa , Labor laws and legislation -- South Africa , Medical screening -- South Africa , Industrial hygiene -- South Africa
  • Description: South Africa’s Constitution and the Employment Equity Act have a major impact on the performance of medical examinations within the employment relationship. Health and safety statutes list a number of occupational medical examinations, which an employer must perform. Other legislation permits the execution of medical examinations. After listing the different statutory references to occupational medical examinations, this treatise examines under which conditions medical testing is required or permissible. The fairness of employment discrimination based on medical facts, employment conditions, social policy, distribution of employee benefits and inherent job requirement is analysed through a study of the legal texts, experts’ opinions and case studies. The particularities of the ethical and legal duties of the medical professional, performing the occupational medical examination, are also examined. Finally, a comprehensive analysis of the different forms of occupational medical examinations is compiled by combining legal and policy-related job requirements and is attached as an annexure. This is the practical result of the research in this treatise combined with the personal experience of the author.
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  • Date Issued: 2003

On the use of metabolic rate measurements to assess the stress response in juvenile spotted grunter, Pomadasys commersonnii (Haemulidae, Pisces)

  • Authors: Radull, John
  • Date: 2003
  • Subjects: Fishes -- Metabolism Fishes -- Physiology Pomadasys -- Physiology Grunts (Fishes) -- Physiology Stress (Psychology) Stress (Physiology)
  • Language: English
  • Type: Thesis , Doctoral , PhD
  • Identifier: vital:5350 , http://hdl.handle.net/10962/d1007564
  • Description: Quantitication of stress requires the use of a stress indicator that is easy to measure, and which can be readily interpreted in terms of the potential long-term effects to an organism. This study evaluates the suitability of metabolic rate as an indicator of the stress response in fish. By comparing the metabolic with the cortisol stress response, the most commonly used indicator of stress in fish, it was possible to assess the suitability of metabolic rate as a stress indicator. Changes in metabolic rate were used to predict the long-term effects of transport-related stressors. This study also detennined the baseline metabolic rates of the tish. The standard and the active metabolic rates of juvenile P. cummersonnii were 0.16 ± 0.02 (mean ± S.D, n = 6) mg O₂g⁻¹h⁻¹, and 0.56 ± 0.04 mg O₂g⁻¹h⁻¹, respectively, whereas the routine metabolic rate for the fish was 0.25 ± 0.03 mg O₂g⁻¹h¹. The relationship between metabolic rate and body weight was described by the equation ϺO₂ = 0.64 W⁻°·³⁸. 24-h oxygen consumption measurements showed that juvenile P. commersonnii exhibited diel rhythmicity in oxygen consumption rate, the higher rates occurring at night and the lower rates during the daytime. The higher nocturnal metabolic activity may have been due to increased activity induced by an endogenous rhythm related to feeding. Diel rhythmicity has direct implications for the measurement of baseline metabolic rates since it could result in overestimation or underestimation of these rates. 24-h continuous oxygen consumption measurements enabled the detection of the rhythmicity in oxygen consumption rate, and thereby ensured a greater degree of accuracy in the estimation of these parameters. The metabolic stress response in juvenile P. commersonnii was best described by the equation, y = -0.0013 x² + 0.0364 x ÷ 0.3052, where x = time after application of stressor, and y = oxygen consumption rate. Using the derivative of this equation, the metabolic stress response was estimated to peak approximately 14 min after application of a simulated capture and handling stressor. Oxygen consumption increased by about 300 % as a result of the stress. Approximately 15 min after application of a similar stressor, plasma cortisol levels in stressed fish was 200 % higher than baseline levels. However, cortisol levels in fish sampled 30 min after the disturbance was similar to the baseline cortisol levels, indicating that full recovery had occurred. Although the patterns in the metabolic and cortisol stress responses were similar, metabolic rate could be measured continuously, thereby ensuring accurate interpretation of the data. Furthermore, increases in metabolic rate during the stress response are a culmination of physiological events from the primary to the tertiary levels of biological organization and are, therefore, easier to interpret in terms of long-term effects on the fish. Different transportation procedures elicited variable degrees of stress in juvenile P. commersonnii. The cost of metabolism attributed to the effects of capture and handling was twice as much as that attributed to acute temperature elevation. Acute temperature decrease resulted in a signiticant reduction in the oxygen consumption rate (ANOVA, P < 0.05). Oxygen consumption by the fish was not affected by fish density (ANOVA: F = 2.002, P = 0.5), or by oxygen depletion at dissolved oxygen concentrations above the critical level. Below this level, however, oxygen consumption decreased linearly with further decrease in dissolved oxygen concentration. These results showed that the highest energetic cost to juvenile P. commersonnii was incurred as a result of capture and handling. The results also showed that by subjecting fish to different stressors, it was possible to categorize them according to their relative metabolic costs to the fish. At 25º C, the effective concentration of 2-phenoxyethanol to fully anaesthetize (Stage IV, McFarland 1960) juvenile P. commersonnii was 0.4 ml l⁻¹ and the most appropriate concentration for deep sedation (Stage II, McFarland 1960) of the fish for at least 24 h was 0.2 ml l⁻¹. A maximum of 3 minutes was required by the fish to recover from the effects of the anaesthetic. There was no correlation between fish weight and the rate of induction of anaesthesia (r² = 0.001, p = 0.3). At the peak of the metabolic stress response, oxygen consumption was twice as high in the un-anaesthetized fish compared to the fish anaesthetized after the application of the simulated capture and handling stressor, suggesting that anaesthetization with 2-phenoxyethanol may have reduced the effect of the disturbance on the fish. Similar oxygen consumption rates for the fish anaesthetized prior to capture and the non-stressed fish suggested that the increases in metabolic rate could be linked to the struggling associated with attempts by fish to escape from the perceived stressor. Anaesthetization of juvenile P. commersonnii with 0.3 ml l⁻¹ 2-phenoxyethanol resulted in a more than 200 % increase in plasma cortisol concentration. The elevated levels of plasma cortisol in the anaesthetized fish suggested a manifestation of 2-phenoxyethanol as a stressor. At the time of capture, cortisol levels in fish that were anaesthetized prior to capture were the same as those measured in the disturbed fish at the peak of the stress response (ANOVA, p = 0.95), suggesting that the anaesthetized fish were already experiencing considerable stress at the time they were captured. Undisturbed juvenile P. commersonnii that were anaesthetized for 1 h also had cortisol levels that were five times higher than those measured in undisturbed-unanaesthetized fish, indicating that the duration of exposure to the anaesthetic had a significant effect on plasma cortisol levels. The results presented in this study demonstrate the usefulness of metabolic rate as an indicator of acute stress in fish. This was achieved by comparing the metabolic and the cortisol stress responses. The ease and accuracy with which oxygen consumption of fish could be measured made it possible to measure the stress response more accurately than by plasma cortisol concentration. It was also possible to monitor metabolic rate continuously over a long duration using polarographic oxygen sensors, thus enabling a better evaluation of the stress response. These results, thus, suggest that metabolic rate measurements could be a more practical way to quantify the effects of acute stressors on juvenile fishes. By detailing the profile of the metabolic stress response in P. commersonnii, this study makes a contribution towards understanding the physiological effects of stress in fishes. The study also contributes towards the quantification of baseline metabolic rates of this species under captivity. This study also contributes towards understanding the effects of 2-phenoxyethanol on the stress physiology of fish. By anaesthetizing fish under different conditions of stress, it was possible to evaluate the effect of 2-phenoxyethanol on the metabolic stress response. The ability of 2-phenoxyethanol to reduce physical activity of the fish, and thereby reduce the impact of acute stress on the metabolic stress response, makes it a good agent for the mitigation of stress during the capture and handling of fish. However, the increase in plasma cortisol concentration during prolonged anaesthetization using this drug suggests that the anaesthetic might be a stressor to fish and may, therefore, not be suitable for long-term sedation.
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  • Date Issued: 2003

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.
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  • 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.
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  • 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
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  • 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.
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  • 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.
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  • 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.
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  • 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
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  • 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.
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  • 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.
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  • Date Issued: 2003

Pharmaceutical Pictograms: Part 1: Communicating Medicine Information to the Low-literate Patient

  • 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.
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  • Date Issued: 2003

Pharmaceutical Pictograms: part 2: weird and wonderful interpretations

  • 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
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