Ph-responsive liposomal systems for site-specific pulmonary delivery of anti-tubercular drugs
- Nkanga, Christian Isalomboto
- Authors: Nkanga, Christian Isalomboto
- Date: 2019
- Subjects: Tuberculosis -- Chemotherapy , Lipsomes , Drug carriers (Pharmacy) , Rifampin , Hydrogen-ion concentration , Hydrogen-ion concentration -- Physiological effect
- Language: English
- Type: text , Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/125832 , vital:35822
- Description: Tuberculosis (TB) is an infectious disease that has been reported to be the ninth leading cause of death worldwide, even though mostly considered as a poverty related disease. Despite the existence of potent anti-tubercular drugs (ATBDs), such as rifampicin (RIF) and isoniazid (INH), TB remains the major killer among many microbial diseases over the last five years. Although several factors are to be blamed for this deadly status, the most crucial issues encompass both the self-defensiveness of the causative agent (Mycobacterium tuberculosis), including its intra-macrophage location that compromises ATBDs accessibility, and the widespread/off target distribution of ATBDs. The need for novel drug delivery strategies therefore arises to provide selective distribution of ATBDs at the infected site. Among the drug vehicles explored in this field, liposomes have been reported to be the most suitable drug carriers due to their rapid uptake by alveolar macrophages, where M. tuberculosis often resides. Since liposomes experience media of different pH throughout the cell uptake process (endocytosis/phagocytosis), the use of pH change as a stimulus for controlled release looks promising for enhancing intra-macrophage delivery and minimizing premature ‘off-target’ release of ATBDs. However, the costly status of liposome technology, due to the use of sophisticated procedures and expensive materials (especially for pH-dependent delivery, where special lipids are required), may preclude wider developments of liposomal products, especially for the developing world. This study aimed at investigating liposomal encapsulation of pH-sensitive and fluorescent hydrazone derivatives of INH using crude soybean lecithin, as a cost-effective option for site-specific delivery combined with potential bio-imaging features. Another objective was to explore encapsulation of INH hydrazone derivatives with and without RIF in liposomes using a simple and organic solvent-free preparation method. Initially, INH was coupled with 4-hydroxy-benzaldehyde to yield a conjugate (INH-HB) that was encapsulated in liposomes using film hydration method with acceptable encapsulation efficiency (î), about 89 %. The prepared INH-HB loaded liposomes (IHL) were characterized by means of dynamic light scattering (DLS), transmission electron microscopy (TEM), differential scanning calorimetry (DSC) and X-ray diffraction (XRD). The release of INH from IHL was evaluated over 12 hours in media of different pH using dialysis. As hypothesized, pH dependent release of INH from IHL was observed with 22, 69, 83 and 100 % release obtained in media of pH 7.4, 6.4, 5.4 and 4.4, respectively. From this experimental trial, further development was undertaken by conjugating INH to a hydrophobic fluorescent tag, zinc (II) phthalocyanine (PC), through hydrazone linkages. The obtained conjugate (PC-INH) was loaded into liposomes (PIL) that were characterized using various spectroscopic techniques, including UV-Vis absorption and energy dispersive X-ray spectroscopy, which suggested the presence of PC-INH within the lipid bilayers. The release study performed in different pH media revealed 22, 41, 97 and 100 % of INH, respectively released at pH 7.4, 6.4, 5.4 and 4.4. This confirmed the potential of pH-triggered drug release from liposomes loaded with hydrazone drug derivatives. In addition, successful encapsulation of PC-INH using crude soybean lecithin inspired a new opening towards development of multimodal liposomes that could achieve controlled drug release with added benefits of image-guided biological tracking. However, the hydrophobic nature of PC-INH requires an effective strategy that could improve its solubility and favour extensive development. In this context, the tetra-substituted structure of PC-INH brought up the hypothesis that cyclodextrin (CD) complexation would facilitate PC-INH encapsulation in liposomes using an organic solvent-free method, called here the “heating method” (HM). Inclusion complexes of PC-INH with various CDs were therefore investigated, with gamma-CD complex (CP) giving the best results. These complexes were prepared in both solution and solid-state and further comprehensively characterized using UV-Vis spectroscopy, magnetic circular dichroism, NMR spectroscopy, diffusion ordered spectroscopy, DSC, XRD and Fourier transform infrared spectroscopy. CP-loaded liposomes prepared using HM exhibited greater î than film hydration liposomes, about 70 % versus 56 %, respectively. The HM-liposomal system (CPL) exhibited potentially useful nano particulate characteristics (i.e. mean particle size 240 nm and Zeta potential –57 mV), which remained unchanged over 5 weeks of stability study at 4 °C, and pH-dependent INH release behaviour alike PIL. Furthermore, CP was co-encapsulated with rifampicin (RIF) in liposomes using HM to investigate the possibility for future combination therapy. 1H-NMR spectroscopy, DSC, XRD and photophysical studies were performed for molecular assessment of the cargo in CP-RIF co-loaded liposomes (CPRL). The mean particle size, Zeta potential and î of CPRL were respectively 594 nm, –50 mV, 58 % for CP and 86 % for RIF. CPRL exhibited much higher release rates for both INH and RIF at pH 6.4, compared to those tested at pH 7.4. In addition, there was no cytotoxicity on HeLa cells, but attractive lung fibroblasts and epithelial cells uptake and viability. Hence, CPRL are promising for targeted ATBD delivery to alveolar macrophages following pulmonary administration. Overall, the developed pH-responsive liposomal system holds the promise for new openings towards wider developments of multifunctional liposomes for site-specific controlled pulmonary delivery of antimicrobials drugs.
- Full Text:
- Date Issued: 2019
- Authors: Nkanga, Christian Isalomboto
- Date: 2019
- Subjects: Tuberculosis -- Chemotherapy , Lipsomes , Drug carriers (Pharmacy) , Rifampin , Hydrogen-ion concentration , Hydrogen-ion concentration -- Physiological effect
- Language: English
- Type: text , Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/125832 , vital:35822
- Description: Tuberculosis (TB) is an infectious disease that has been reported to be the ninth leading cause of death worldwide, even though mostly considered as a poverty related disease. Despite the existence of potent anti-tubercular drugs (ATBDs), such as rifampicin (RIF) and isoniazid (INH), TB remains the major killer among many microbial diseases over the last five years. Although several factors are to be blamed for this deadly status, the most crucial issues encompass both the self-defensiveness of the causative agent (Mycobacterium tuberculosis), including its intra-macrophage location that compromises ATBDs accessibility, and the widespread/off target distribution of ATBDs. The need for novel drug delivery strategies therefore arises to provide selective distribution of ATBDs at the infected site. Among the drug vehicles explored in this field, liposomes have been reported to be the most suitable drug carriers due to their rapid uptake by alveolar macrophages, where M. tuberculosis often resides. Since liposomes experience media of different pH throughout the cell uptake process (endocytosis/phagocytosis), the use of pH change as a stimulus for controlled release looks promising for enhancing intra-macrophage delivery and minimizing premature ‘off-target’ release of ATBDs. However, the costly status of liposome technology, due to the use of sophisticated procedures and expensive materials (especially for pH-dependent delivery, where special lipids are required), may preclude wider developments of liposomal products, especially for the developing world. This study aimed at investigating liposomal encapsulation of pH-sensitive and fluorescent hydrazone derivatives of INH using crude soybean lecithin, as a cost-effective option for site-specific delivery combined with potential bio-imaging features. Another objective was to explore encapsulation of INH hydrazone derivatives with and without RIF in liposomes using a simple and organic solvent-free preparation method. Initially, INH was coupled with 4-hydroxy-benzaldehyde to yield a conjugate (INH-HB) that was encapsulated in liposomes using film hydration method with acceptable encapsulation efficiency (î), about 89 %. The prepared INH-HB loaded liposomes (IHL) were characterized by means of dynamic light scattering (DLS), transmission electron microscopy (TEM), differential scanning calorimetry (DSC) and X-ray diffraction (XRD). The release of INH from IHL was evaluated over 12 hours in media of different pH using dialysis. As hypothesized, pH dependent release of INH from IHL was observed with 22, 69, 83 and 100 % release obtained in media of pH 7.4, 6.4, 5.4 and 4.4, respectively. From this experimental trial, further development was undertaken by conjugating INH to a hydrophobic fluorescent tag, zinc (II) phthalocyanine (PC), through hydrazone linkages. The obtained conjugate (PC-INH) was loaded into liposomes (PIL) that were characterized using various spectroscopic techniques, including UV-Vis absorption and energy dispersive X-ray spectroscopy, which suggested the presence of PC-INH within the lipid bilayers. The release study performed in different pH media revealed 22, 41, 97 and 100 % of INH, respectively released at pH 7.4, 6.4, 5.4 and 4.4. This confirmed the potential of pH-triggered drug release from liposomes loaded with hydrazone drug derivatives. In addition, successful encapsulation of PC-INH using crude soybean lecithin inspired a new opening towards development of multimodal liposomes that could achieve controlled drug release with added benefits of image-guided biological tracking. However, the hydrophobic nature of PC-INH requires an effective strategy that could improve its solubility and favour extensive development. In this context, the tetra-substituted structure of PC-INH brought up the hypothesis that cyclodextrin (CD) complexation would facilitate PC-INH encapsulation in liposomes using an organic solvent-free method, called here the “heating method” (HM). Inclusion complexes of PC-INH with various CDs were therefore investigated, with gamma-CD complex (CP) giving the best results. These complexes were prepared in both solution and solid-state and further comprehensively characterized using UV-Vis spectroscopy, magnetic circular dichroism, NMR spectroscopy, diffusion ordered spectroscopy, DSC, XRD and Fourier transform infrared spectroscopy. CP-loaded liposomes prepared using HM exhibited greater î than film hydration liposomes, about 70 % versus 56 %, respectively. The HM-liposomal system (CPL) exhibited potentially useful nano particulate characteristics (i.e. mean particle size 240 nm and Zeta potential –57 mV), which remained unchanged over 5 weeks of stability study at 4 °C, and pH-dependent INH release behaviour alike PIL. Furthermore, CP was co-encapsulated with rifampicin (RIF) in liposomes using HM to investigate the possibility for future combination therapy. 1H-NMR spectroscopy, DSC, XRD and photophysical studies were performed for molecular assessment of the cargo in CP-RIF co-loaded liposomes (CPRL). The mean particle size, Zeta potential and î of CPRL were respectively 594 nm, –50 mV, 58 % for CP and 86 % for RIF. CPRL exhibited much higher release rates for both INH and RIF at pH 6.4, compared to those tested at pH 7.4. In addition, there was no cytotoxicity on HeLa cells, but attractive lung fibroblasts and epithelial cells uptake and viability. Hence, CPRL are promising for targeted ATBD delivery to alveolar macrophages following pulmonary administration. Overall, the developed pH-responsive liposomal system holds the promise for new openings towards wider developments of multifunctional liposomes for site-specific controlled pulmonary delivery of antimicrobials drugs.
- Full Text:
- Date Issued: 2019
Aiding the education agenda? the role of non-governmental organisations in learner performance and retention in Joza, Grahamstown, South Africa
- Authors: Nomsenge, Sinazo Onela
- Date: 2019
- Subjects: Non-governmental organizations , Non-governmental organizations -- South Africa -- Makhanda , Black people -- Education -- South Africa -- Makhanda , Education -- South Africa -- Makhanda , Joza Youth Hub (Makhanda) , Upstart Youth Development Project (Makhanda) , Village Scribe Association (Makhanda) , Ikamba Youth (Makhanda) , Access Music Project(Makhanda)
- Language: English
- Type: text , Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/76468 , vital:30568
- Description: This thesis describes the network of complexities that characterise the world and work of Non-Governmental Organisations (NGOs). It examines the ways in which organisations navigate different internal, sectoral and contextual intricacies while operating under the command of their chosen developmental mandates. This description is drawn from a sociological analysis of the internal workings of education NGOs, their external affiliations as well as the negotiations which underpin their operations and survival. Collectively, the careful illustration of these underpinnings outlines both the role that NGOs play in the performance and retention of learners in the Grahamstown-east township of Joza and also their position in the town’s basic education sector. Private and non-governmental interveners have, particularly from the closing decades of the 20th century, been conceptually and operationally deployed as panaceas of the socio-economic scarcities which continue to pervade much of the ‘developing’ world. Their involvement in the socio-economic missions of populations living in the Global South has grown both laterally and in the depth of how development is understood and defined, carried out and also measured. NGOs, as widely acclaimed institutional arms of global development imperatives, therefore assume prominent positions in framing policy and implementation models, prescribing performance benchmarks and pronouncing non-compliance. Likewise, education NGOs have obtained normative prescription status in global education policy and practice largely on the back of the Education for All (EFA) objectives, the Millennium Development Goals (MDGs) and the neo-liberal logics which have championed state retreat in favour of private sector ascendance in globalised development. This, in conjunction with the persistent struggles of educational transformation in the Global South, has given NGOs little trouble in legitimising their prominent presence in education and other sectors of socio-economic relief in these parts of the world. Little illusion remains however, in many commentary circles, of the role of NGOs in advancing development ideals, the honesty of their altruistic intents, their ideological leanings as well as their efficacy in carrying out their mandates. As such, the logics which have been used to dethrone developing state structures in order to expand the space for private intervention along with the prevailing and deepening markers of educational underperformance, have been central features of the criticisms levelled against NGOs. This thesis intervenes in these ongoing reflections by describing the role of NGOs in educational outcomes, particularly learner performance and retention in Joza. This analysis demonstrates the organisational, sector-level and broader community forces which influence not only the form which non-state interventions take on and the daily preoccupations of their carriers but broadly, the position they occupy in the town’s overall educational profile. By way of locating NGOs within Grahamstown’s educational landscape, this thesis first demonstrates, the conflicted nature of NGO operations from an international, sectoral, national, local and organisational level. The discussion then illustrates how the preoccupations of NGOs are scattered between the different communities which they occupy within these levels. Their reliance on these players demands that organisations be tactical in guarding both their survival and, at times, the conflicting allegiances which grant them different forms of legitimacy. Internal struggles which characterise this imbalance of forces results in a trade-off which often favours organisational preservation mechanisms over systemic educational overhaul. As such, while non-state interveners can be lauded for extending educational support to those who would otherwise not have such, the gains of NGO intervention are often absorbed by internal urgencies for organisational legitimacy and preservation. This, in a context which possesses a unique set of socio-economic and educational deficits that require, at the very least, radical and unbridled mediation, means that pre-existing inequalities in educational inputs and outcomes along with the resultant inequities in youth socio-economic prospects, can find refuge in the very sector whose support and intervention is sought out and justified for such. This thesis lays out the nuances of these tensions and contradictions and offers this case as a point of reference for further considerations of the persistent markers of underperformance which characterise developing communities that enjoy high concentrations of non-state educational intervention.
- Full Text:
- Date Issued: 2019
- Authors: Nomsenge, Sinazo Onela
- Date: 2019
- Subjects: Non-governmental organizations , Non-governmental organizations -- South Africa -- Makhanda , Black people -- Education -- South Africa -- Makhanda , Education -- South Africa -- Makhanda , Joza Youth Hub (Makhanda) , Upstart Youth Development Project (Makhanda) , Village Scribe Association (Makhanda) , Ikamba Youth (Makhanda) , Access Music Project(Makhanda)
- Language: English
- Type: text , Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/76468 , vital:30568
- Description: This thesis describes the network of complexities that characterise the world and work of Non-Governmental Organisations (NGOs). It examines the ways in which organisations navigate different internal, sectoral and contextual intricacies while operating under the command of their chosen developmental mandates. This description is drawn from a sociological analysis of the internal workings of education NGOs, their external affiliations as well as the negotiations which underpin their operations and survival. Collectively, the careful illustration of these underpinnings outlines both the role that NGOs play in the performance and retention of learners in the Grahamstown-east township of Joza and also their position in the town’s basic education sector. Private and non-governmental interveners have, particularly from the closing decades of the 20th century, been conceptually and operationally deployed as panaceas of the socio-economic scarcities which continue to pervade much of the ‘developing’ world. Their involvement in the socio-economic missions of populations living in the Global South has grown both laterally and in the depth of how development is understood and defined, carried out and also measured. NGOs, as widely acclaimed institutional arms of global development imperatives, therefore assume prominent positions in framing policy and implementation models, prescribing performance benchmarks and pronouncing non-compliance. Likewise, education NGOs have obtained normative prescription status in global education policy and practice largely on the back of the Education for All (EFA) objectives, the Millennium Development Goals (MDGs) and the neo-liberal logics which have championed state retreat in favour of private sector ascendance in globalised development. This, in conjunction with the persistent struggles of educational transformation in the Global South, has given NGOs little trouble in legitimising their prominent presence in education and other sectors of socio-economic relief in these parts of the world. Little illusion remains however, in many commentary circles, of the role of NGOs in advancing development ideals, the honesty of their altruistic intents, their ideological leanings as well as their efficacy in carrying out their mandates. As such, the logics which have been used to dethrone developing state structures in order to expand the space for private intervention along with the prevailing and deepening markers of educational underperformance, have been central features of the criticisms levelled against NGOs. This thesis intervenes in these ongoing reflections by describing the role of NGOs in educational outcomes, particularly learner performance and retention in Joza. This analysis demonstrates the organisational, sector-level and broader community forces which influence not only the form which non-state interventions take on and the daily preoccupations of their carriers but broadly, the position they occupy in the town’s overall educational profile. By way of locating NGOs within Grahamstown’s educational landscape, this thesis first demonstrates, the conflicted nature of NGO operations from an international, sectoral, national, local and organisational level. The discussion then illustrates how the preoccupations of NGOs are scattered between the different communities which they occupy within these levels. Their reliance on these players demands that organisations be tactical in guarding both their survival and, at times, the conflicting allegiances which grant them different forms of legitimacy. Internal struggles which characterise this imbalance of forces results in a trade-off which often favours organisational preservation mechanisms over systemic educational overhaul. As such, while non-state interveners can be lauded for extending educational support to those who would otherwise not have such, the gains of NGO intervention are often absorbed by internal urgencies for organisational legitimacy and preservation. This, in a context which possesses a unique set of socio-economic and educational deficits that require, at the very least, radical and unbridled mediation, means that pre-existing inequalities in educational inputs and outcomes along with the resultant inequities in youth socio-economic prospects, can find refuge in the very sector whose support and intervention is sought out and justified for such. This thesis lays out the nuances of these tensions and contradictions and offers this case as a point of reference for further considerations of the persistent markers of underperformance which characterise developing communities that enjoy high concentrations of non-state educational intervention.
- Full Text:
- Date Issued: 2019
Descriptive guidelines for mediation to enhance the parental involvement of unmarried fathers
- Authors: Nordien-Lagardien, Razia
- Date: 2019
- Subjects: Mediation , Unmarried fathers -- South Africa Father and child -- South Africa Unmarried mothers -- South Africa
- Language: English
- Type: Thesis , Doctoral , DPhil
- Identifier: http://hdl.handle.net/10948/30462 , vital:30948
- Description: A significant change brought about by the Children’s Act 38 of 2005 (RSA, 2006), is that of the status of unmarried fathers. The parental rights of unmarried fathers have evolved in South Africa, especially since the Children’s Act 38 of 2005 (RSA, 2006) now recognises that unmarried fathers should have inherent right of contact, guardianship and care. These rights are, however, not automatic and need to be acquired through a process of mediation. While this legislation aims to facilitate the parental involvement of fathers by giving them rights as per Section 21 of the Children’s Act 38 of 2005 (RSA, 2006), the reality is that many unmarried fathers still remain challenged in this regard despite the change in their legal position as fathers. Unmarried fathers are often compelled to take the matter further through protracted court processes. Unmarried fathers face unique challenges with parental involvement after separation and they often need to negotiate their involvement with the mother after separation. Given that mediation between unmarried parents is in its infancy in South Africa, very little research has been done in this area. It was envisaged that this study would highlight the important aspects of mediation which need to be considered in order for mediation outcomes to be more successful and to enhance the co-parenting relationship. The study employed a qualitative research approach that was exploratory, descriptive and contextual in design. The research study consisted of three phases. Phase 1 employed a multiple case study design in order to develop an understanding of the experiences and perceptions of unmarried fathers and mothers, as well as mediators, regarding the parental responsibilities of unmarried fathers in addition to their experiences of mediation. The data collection process comprised in-depth semi-structured interviews with three sample groups, namely unmarried fathers, and mothers, and mediators. The data collected from the interviews were transcribed, coded and analysed by the researcher through the use of two techniques, namely: within-case analysis and cross-case synthesis. An independent coder was utilised to verify the coding and analysis process. The analysis of the data in Phase 1 revealed that the construction of the role of unmarried fathers is influenced by various factors such as cultural and religious influences; childhood experiences of fatherhood; societal constructions of the father’s role, and the perception of the legal rights of unmarried fathers. The new legislation pertaining to the responsibilities and rights of unmarried fathers, as contained in the Children’s Act 38 of 2005 (RSA, 2006), has resulted in increased parental conflict between parents after separation owing to their lack of awareness and confusion regarding the changes in legislation pertaining to the rights of unmarried fathers and the role of customary law in this regard. This has resulted in misconceptions about the legal rights of unmarried fathers, which have influenced unmarried parents’ attitudes and receptiveness to mediation. A significant barrier to father involvement emanating from the findings was relationship conflict experienced after separation, which was also identified as a significant challenge in mediation. The discussion of the themes reflected both positive and negative experiences of mediation for the study participants. While the parents derived educational and therapeutic benefits from mediation; there were also several factors such as relationship conflict, cultural barriers, influences of the extended family, and the approach and skills of the mediator, which influenced the mediation process. In Phase 2 of the study an integrative literature review and synthesis of the literature was conducted and critically appraised in terms of emergent themes and relevant research in the area of family mediation, which would inform the process of developing the descriptive guidelines for mediation with unmarried parents. The empirical findings from the study were synthesised with the findings from the integrative literature review, thus enabling conclusions to be drawn in order to generate descriptive guidelines for mediation. Phase 3 of the study describes the guidelines for mediation which emanated from the synthesis of the findings in Phase 1 and Phase 2 of the study. As part of a qualitative evaluation, the guidelines were presented to an expert panel for review, after which the guidelines were finalised. The proposed guidelines for mediation to enhance the parental involvement of unmarried fathers is based on the hybrid model of mediation, which incorporates elements from the Transformative approach, the African centred approach and the co-mediation model. The guidelines are further described in terms of a phased approach to mediation.
- Full Text:
- Date Issued: 2019
- Authors: Nordien-Lagardien, Razia
- Date: 2019
- Subjects: Mediation , Unmarried fathers -- South Africa Father and child -- South Africa Unmarried mothers -- South Africa
- Language: English
- Type: Thesis , Doctoral , DPhil
- Identifier: http://hdl.handle.net/10948/30462 , vital:30948
- Description: A significant change brought about by the Children’s Act 38 of 2005 (RSA, 2006), is that of the status of unmarried fathers. The parental rights of unmarried fathers have evolved in South Africa, especially since the Children’s Act 38 of 2005 (RSA, 2006) now recognises that unmarried fathers should have inherent right of contact, guardianship and care. These rights are, however, not automatic and need to be acquired through a process of mediation. While this legislation aims to facilitate the parental involvement of fathers by giving them rights as per Section 21 of the Children’s Act 38 of 2005 (RSA, 2006), the reality is that many unmarried fathers still remain challenged in this regard despite the change in their legal position as fathers. Unmarried fathers are often compelled to take the matter further through protracted court processes. Unmarried fathers face unique challenges with parental involvement after separation and they often need to negotiate their involvement with the mother after separation. Given that mediation between unmarried parents is in its infancy in South Africa, very little research has been done in this area. It was envisaged that this study would highlight the important aspects of mediation which need to be considered in order for mediation outcomes to be more successful and to enhance the co-parenting relationship. The study employed a qualitative research approach that was exploratory, descriptive and contextual in design. The research study consisted of three phases. Phase 1 employed a multiple case study design in order to develop an understanding of the experiences and perceptions of unmarried fathers and mothers, as well as mediators, regarding the parental responsibilities of unmarried fathers in addition to their experiences of mediation. The data collection process comprised in-depth semi-structured interviews with three sample groups, namely unmarried fathers, and mothers, and mediators. The data collected from the interviews were transcribed, coded and analysed by the researcher through the use of two techniques, namely: within-case analysis and cross-case synthesis. An independent coder was utilised to verify the coding and analysis process. The analysis of the data in Phase 1 revealed that the construction of the role of unmarried fathers is influenced by various factors such as cultural and religious influences; childhood experiences of fatherhood; societal constructions of the father’s role, and the perception of the legal rights of unmarried fathers. The new legislation pertaining to the responsibilities and rights of unmarried fathers, as contained in the Children’s Act 38 of 2005 (RSA, 2006), has resulted in increased parental conflict between parents after separation owing to their lack of awareness and confusion regarding the changes in legislation pertaining to the rights of unmarried fathers and the role of customary law in this regard. This has resulted in misconceptions about the legal rights of unmarried fathers, which have influenced unmarried parents’ attitudes and receptiveness to mediation. A significant barrier to father involvement emanating from the findings was relationship conflict experienced after separation, which was also identified as a significant challenge in mediation. The discussion of the themes reflected both positive and negative experiences of mediation for the study participants. While the parents derived educational and therapeutic benefits from mediation; there were also several factors such as relationship conflict, cultural barriers, influences of the extended family, and the approach and skills of the mediator, which influenced the mediation process. In Phase 2 of the study an integrative literature review and synthesis of the literature was conducted and critically appraised in terms of emergent themes and relevant research in the area of family mediation, which would inform the process of developing the descriptive guidelines for mediation with unmarried parents. The empirical findings from the study were synthesised with the findings from the integrative literature review, thus enabling conclusions to be drawn in order to generate descriptive guidelines for mediation. Phase 3 of the study describes the guidelines for mediation which emanated from the synthesis of the findings in Phase 1 and Phase 2 of the study. As part of a qualitative evaluation, the guidelines were presented to an expert panel for review, after which the guidelines were finalised. The proposed guidelines for mediation to enhance the parental involvement of unmarried fathers is based on the hybrid model of mediation, which incorporates elements from the Transformative approach, the African centred approach and the co-mediation model. The guidelines are further described in terms of a phased approach to mediation.
- Full Text:
- Date Issued: 2019
Microalgae as indicators of environmental change in the St Lucia estuarine system
- Authors: Nunes, Monique
- Date: 2019
- Subjects: Microalgae -- South Africa -- St Lucia estuarine
- Language: English
- Type: Thesis , Doctoral , DPhil
- Identifier: http://hdl.handle.net/10948/31165 , vital:31333
- Description: The St Lucia system represents 56% of the estuarine habitat area in South Africa. This dynamic estuarine lake responds to a complex interaction of climatic and anthropogenic drivers. There has been a long history of human interventions and the extended drought (2002-2012) led to major changes. In 1952, the inlet shared between the estuarine system and the Mfolozi River was artificially separated, which significantly reduced freshwater inflow. The systems were separated because of the silt load from the expanding agricultural activities in the Mfolozi River catchment. The drought prompted a critical review of re-establishing the historic connection, and in July 2012, the beach spillway was excavated marking the start of restoring connectivity. Increased rainfall coupled with the partial re-connection with the agriculturally-impacted Mfolozi River shifted the St Lucia estuarine system to a new wet phase. This study investigated the microalgal dynamics of the estuarine system as it transitioned to this new wet phase. Results showed that the phytoplankton and microphytobenthos (MPB) biomass was low (< 5 ug l-1 and < 60 mg m-2 respectively) throughout the system due to nutrient and light availability, water residence time and sediment type. The increased freshwater inflow from the Mfolozi River was limited to the Narrows and available nutrients promoted the growth of cyanobacteria and dinophytes in the water column. Of interest was the presence of the potentially harmful algal species Prorocentrum minimum. A weekly study investigated the relationship between freshwater inflow, phytoplankton succession and the introduction and persistence of harmful microalgal species in the lower reaches. The increased freshwater inflow received from the Mfolozi River has led to a system in a constant state of flux. The changes in salinity, light availability and water residence time, shifted the phytoplankton functional group structure to one where chlorophytes and euglenoids were dominant. The persistence of the nutrient tolerant euglenoids highlighted the influence of the nutrient-enriched freshwater inflow on the phytoplankton functional groups. However, the relative abundance of all functional groups remained low due to the rapid change in environmental conditions. The next step was to test the use of an artificial substrate as a monitoring method to detect nutrient induced change. Findings from the 28-day study showed that epilithic diatom communities growing on glass slides were good indicators of nutrient enrichment. The epilithic algal biomass increased significantly from 1.5 mg m-2 (Day 14) to 6 mg m-2 (Day 21), following peak river inflow. In contrast, the phytoplankton and MPB showed no discernible increase in biomass. Epilithic diatom community diversity, richness and evenness scores declined due to the increasing relative abundance of a single nutrient tolerant species, Cocconeis placentula var. euglypta. The use of diatoms as indicators of change depends on the accuracy of identification to species level. This can be a slow process requiring a high level of taxonomic expertise. Considering that molecular phylogenetic methods are readily used to produce a reliable taxonomic list, the suitability of DNA metabarcoding for diatom monitoring in the St Lucia Estuary was tested. Comparisons between the molecular and morphological method indicated that the diatom taxonomic composition was similar at 9 to 27% for genus level and 2 to 9% at species level. The low taxonomic similarity was related to the large number of unclassified DNA representative sequences included in the molecular inventory due to the incomplete DNA library database. However, the available operational taxonomic units (OTUs) from the molecular method did provide an effective alternative to determine the relevant community diversity estimates required for the application of the South African Estuarine Health Index (EHI). This research has highlighted the dynamic nature of the St Lucia estuarine system and the effectiveness of the microalgal communities to differentiate between the cyclical climatic phases and anthropogenic stressors such as nutrient enrichment.
- Full Text:
- Date Issued: 2019
- Authors: Nunes, Monique
- Date: 2019
- Subjects: Microalgae -- South Africa -- St Lucia estuarine
- Language: English
- Type: Thesis , Doctoral , DPhil
- Identifier: http://hdl.handle.net/10948/31165 , vital:31333
- Description: The St Lucia system represents 56% of the estuarine habitat area in South Africa. This dynamic estuarine lake responds to a complex interaction of climatic and anthropogenic drivers. There has been a long history of human interventions and the extended drought (2002-2012) led to major changes. In 1952, the inlet shared between the estuarine system and the Mfolozi River was artificially separated, which significantly reduced freshwater inflow. The systems were separated because of the silt load from the expanding agricultural activities in the Mfolozi River catchment. The drought prompted a critical review of re-establishing the historic connection, and in July 2012, the beach spillway was excavated marking the start of restoring connectivity. Increased rainfall coupled with the partial re-connection with the agriculturally-impacted Mfolozi River shifted the St Lucia estuarine system to a new wet phase. This study investigated the microalgal dynamics of the estuarine system as it transitioned to this new wet phase. Results showed that the phytoplankton and microphytobenthos (MPB) biomass was low (< 5 ug l-1 and < 60 mg m-2 respectively) throughout the system due to nutrient and light availability, water residence time and sediment type. The increased freshwater inflow from the Mfolozi River was limited to the Narrows and available nutrients promoted the growth of cyanobacteria and dinophytes in the water column. Of interest was the presence of the potentially harmful algal species Prorocentrum minimum. A weekly study investigated the relationship between freshwater inflow, phytoplankton succession and the introduction and persistence of harmful microalgal species in the lower reaches. The increased freshwater inflow received from the Mfolozi River has led to a system in a constant state of flux. The changes in salinity, light availability and water residence time, shifted the phytoplankton functional group structure to one where chlorophytes and euglenoids were dominant. The persistence of the nutrient tolerant euglenoids highlighted the influence of the nutrient-enriched freshwater inflow on the phytoplankton functional groups. However, the relative abundance of all functional groups remained low due to the rapid change in environmental conditions. The next step was to test the use of an artificial substrate as a monitoring method to detect nutrient induced change. Findings from the 28-day study showed that epilithic diatom communities growing on glass slides were good indicators of nutrient enrichment. The epilithic algal biomass increased significantly from 1.5 mg m-2 (Day 14) to 6 mg m-2 (Day 21), following peak river inflow. In contrast, the phytoplankton and MPB showed no discernible increase in biomass. Epilithic diatom community diversity, richness and evenness scores declined due to the increasing relative abundance of a single nutrient tolerant species, Cocconeis placentula var. euglypta. The use of diatoms as indicators of change depends on the accuracy of identification to species level. This can be a slow process requiring a high level of taxonomic expertise. Considering that molecular phylogenetic methods are readily used to produce a reliable taxonomic list, the suitability of DNA metabarcoding for diatom monitoring in the St Lucia Estuary was tested. Comparisons between the molecular and morphological method indicated that the diatom taxonomic composition was similar at 9 to 27% for genus level and 2 to 9% at species level. The low taxonomic similarity was related to the large number of unclassified DNA representative sequences included in the molecular inventory due to the incomplete DNA library database. However, the available operational taxonomic units (OTUs) from the molecular method did provide an effective alternative to determine the relevant community diversity estimates required for the application of the South African Estuarine Health Index (EHI). This research has highlighted the dynamic nature of the St Lucia estuarine system and the effectiveness of the microalgal communities to differentiate between the cyclical climatic phases and anthropogenic stressors such as nutrient enrichment.
- Full Text:
- Date Issued: 2019
Observing cosmic reionization with PAPER: polarized foreground simulations and all sky images
- Authors: Nunhokee, Chuneeta Devi
- Date: 2019
- Subjects: Cosmic background radiation , Astronomy -- Observations , Epoch of reionization -- Research , Hydrogen -- Spectra , Radio interferometers
- Language: English
- Type: text , Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/68203 , vital:29218
- Description: The Donald C. Backer Precision Array to Probe the Epoch of Reionization (PAPER, Parsons et al., 2010) was built with an aim to detect the redshifted 21 cm Hydrogen line, which is likely the best probe of thermal evolution of the intergalactic medium and reionization of neutral Hydrogen in our Universe. Observations of the 21 cm signal are challenged by bright astrophysical foregrounds and systematics that require precise modeling in order to extract the cosmological signal. In particular, the instrumental leakage of polarized foregrounds may contaminate the 21 cm power spectrum. In this work, we developed a formalism to describe the leakage due to instrumental widefield effects in visibility-based power spectra and used it to predict contaminations in observations. We find the leakage due to a population of point sources to be higher than the diffuse Galactic emission – for which we can predict minimal contaminations at k>0.3 h Mpc -¹ We also analyzed data from the last observing season of PAPER via all-sky imaging with a view to characterize the foregrounds. We generated an all-sky catalogue of 88 sources down to a flux density of 5 Jy. Moreover, we measured both polarized point source and the Galactic diffuse emission, and used these measurements to constrain our model of polarization leakage. We find the leakage due to a population of point sources to be 12% lower than the prediction from our polarized model.
- Full Text:
- Date Issued: 2019
- Authors: Nunhokee, Chuneeta Devi
- Date: 2019
- Subjects: Cosmic background radiation , Astronomy -- Observations , Epoch of reionization -- Research , Hydrogen -- Spectra , Radio interferometers
- Language: English
- Type: text , Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/68203 , vital:29218
- Description: The Donald C. Backer Precision Array to Probe the Epoch of Reionization (PAPER, Parsons et al., 2010) was built with an aim to detect the redshifted 21 cm Hydrogen line, which is likely the best probe of thermal evolution of the intergalactic medium and reionization of neutral Hydrogen in our Universe. Observations of the 21 cm signal are challenged by bright astrophysical foregrounds and systematics that require precise modeling in order to extract the cosmological signal. In particular, the instrumental leakage of polarized foregrounds may contaminate the 21 cm power spectrum. In this work, we developed a formalism to describe the leakage due to instrumental widefield effects in visibility-based power spectra and used it to predict contaminations in observations. We find the leakage due to a population of point sources to be higher than the diffuse Galactic emission – for which we can predict minimal contaminations at k>0.3 h Mpc -¹ We also analyzed data from the last observing season of PAPER via all-sky imaging with a view to characterize the foregrounds. We generated an all-sky catalogue of 88 sources down to a flux density of 5 Jy. Moreover, we measured both polarized point source and the Galactic diffuse emission, and used these measurements to constrain our model of polarization leakage. We find the leakage due to a population of point sources to be 12% lower than the prediction from our polarized model.
- Full Text:
- Date Issued: 2019
Nonlinear optical responses of targeted phthalocyanines when conjugated with nanomaterials or fabricated into polymer thin films
- Authors: Nwaji, Njemuwa Njoku
- Date: 2019
- Subjects: Electrochemistry , Phthalocyanines , Nanoparticles , Bioconjugates , Thin films , Polymers , Nonlinear optics , Nonlinear optical spectroscopy , Nanostructured materials , Raman effect
- Language: English
- Type: text , Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/71625 , vital:29926
- Description: A number of zinc, gallium and indium metallophthalocyanines (MPcs) with diverse substituents have been synthesized and characterized using various characterization tools such as proton nuclear magnetic resonance (1HNMR), matrix assisted laser desorption time of flight (MALDI-TOF) mass spectrometry, Fourier-transformed infra-red (FT-IR), Ultraviolet-visible (Uv-vis) spectrophotometry, magnetic circular dichroism and CHNS elemental analysis. The time dependent density functional theory was employed to probe the origin of spectroscopic information in these complexes. Complexes with gallium and indium as central metal showed higher triplet quantum yield compared to the zinc derivatives. Some of the MPcs were covalently linked to nanomaterials such as CdTe, CdTeSe, CdTeSe/ZnO, graphene quantum dots (GQDs) as well as metallic gold (AuNPs) and silver (AgNPs) nanoparticles. Others were either surface assembled onto AuNPs and AgNPs or embedded into polystyrene as polymer source. The phthalocyanine-nanomaterial composites (Pc-NMCs) were characterized with FT-IR, UV-visible spectrophotometry, transmission electron microscopy (TEM), dynamic light scattering (DLS), Raman spectroscopy, X-ray photoelectron spectroscopy (XPS) and X-ray diffractometry (XRD). The thickness of the thin films was determined by utilization of the knife edge attachment of the A Bruker D8 Discover X-ray diffraction. The optical limiting properties (using the open-aperture Z-scan technique) of the MPcs and the Pc-NMCs were investigated. The investigated MPcs complexes generally showed good optical limiting properties. The nonlinear optical response of the MPcs were improved in the presence of nanomaterials such as the semiconductor quantum dots (SQDs), graphene quantum dots (GQDs) as well as metallic AuNPs and AgNPs with MPc-QDs showing the best optical limiting behavior. The optical limiting properties of the MPcs were greatly enhanced in the presence of polymer thin films.
- Full Text:
- Date Issued: 2019
- Authors: Nwaji, Njemuwa Njoku
- Date: 2019
- Subjects: Electrochemistry , Phthalocyanines , Nanoparticles , Bioconjugates , Thin films , Polymers , Nonlinear optics , Nonlinear optical spectroscopy , Nanostructured materials , Raman effect
- Language: English
- Type: text , Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/71625 , vital:29926
- Description: A number of zinc, gallium and indium metallophthalocyanines (MPcs) with diverse substituents have been synthesized and characterized using various characterization tools such as proton nuclear magnetic resonance (1HNMR), matrix assisted laser desorption time of flight (MALDI-TOF) mass spectrometry, Fourier-transformed infra-red (FT-IR), Ultraviolet-visible (Uv-vis) spectrophotometry, magnetic circular dichroism and CHNS elemental analysis. The time dependent density functional theory was employed to probe the origin of spectroscopic information in these complexes. Complexes with gallium and indium as central metal showed higher triplet quantum yield compared to the zinc derivatives. Some of the MPcs were covalently linked to nanomaterials such as CdTe, CdTeSe, CdTeSe/ZnO, graphene quantum dots (GQDs) as well as metallic gold (AuNPs) and silver (AgNPs) nanoparticles. Others were either surface assembled onto AuNPs and AgNPs or embedded into polystyrene as polymer source. The phthalocyanine-nanomaterial composites (Pc-NMCs) were characterized with FT-IR, UV-visible spectrophotometry, transmission electron microscopy (TEM), dynamic light scattering (DLS), Raman spectroscopy, X-ray photoelectron spectroscopy (XPS) and X-ray diffractometry (XRD). The thickness of the thin films was determined by utilization of the knife edge attachment of the A Bruker D8 Discover X-ray diffraction. The optical limiting properties (using the open-aperture Z-scan technique) of the MPcs and the Pc-NMCs were investigated. The investigated MPcs complexes generally showed good optical limiting properties. The nonlinear optical response of the MPcs were improved in the presence of nanomaterials such as the semiconductor quantum dots (SQDs), graphene quantum dots (GQDs) as well as metallic AuNPs and AgNPs with MPc-QDs showing the best optical limiting behavior. The optical limiting properties of the MPcs were greatly enhanced in the presence of polymer thin films.
- Full Text:
- Date Issued: 2019
The Moderating Influence of Psychological Empowerment in the relationship between Job Insecurity and Organizational Citizenship Behaviour among the Eastern Cape Department of Health Employees
- Authors: Nwokolo, Echezona E
- Date: 2019
- Subjects: Job security -- South Africa -- Eastern Cape Organizational commitment Employee assistance programs
- Language: English
- Type: Thesis , Doctoral , D.Com (Industrial Psychology)
- Identifier: http://hdl.handle.net/10353/13881 , vital:39722
- Description: The unabated focus of many organizations on competition and profitability has amplified the threats of real or anticipated job loss resulting in the feelings of insecurity for employees about their job and future work life. The research investigated the role of psychological empowerment as moderator of the relationship between job insecurity and organizational citizenship behavior among the Eastern Cape Department of Health employees, in Eastern Cape Province of South Africa. The study adopted an exploratory and correlational research design to understand the relationships that exist between the study variables. Respondents were selected using convenience sampling technique, where a sample size of 357 respondents was selected from sample frame of 4847 employees. Seven-point and Five-point likert scale were used to measure the responses. The data analysis methods used include descriptive statistics, regression analysis, ANOVA and Structural Equation Modeling. The reliability, factor analysis and research hypotheses of the research instruments were tested using the aforementioned statistical techniques. The findings reveal a significant negative correlation between job insecurity and Organizational Citizenship Behaviour, a significant positive correlation between psychological empowerment and OCB. It also revealed that job insecurity and psychological empowerment combined account for a significant higher proportion of variance in OCB than any of the two separately, and that significantly and positively moderates the relationship between job insecurity and OCB. Recommendations to promote psychological empowerment in the organization in order to increase organizational citizenship behavior and decrease job insecurity among employees were suggested to leadership of the government departments, organizations and practicing managers.
- Full Text:
- Date Issued: 2019
- Authors: Nwokolo, Echezona E
- Date: 2019
- Subjects: Job security -- South Africa -- Eastern Cape Organizational commitment Employee assistance programs
- Language: English
- Type: Thesis , Doctoral , D.Com (Industrial Psychology)
- Identifier: http://hdl.handle.net/10353/13881 , vital:39722
- Description: The unabated focus of many organizations on competition and profitability has amplified the threats of real or anticipated job loss resulting in the feelings of insecurity for employees about their job and future work life. The research investigated the role of psychological empowerment as moderator of the relationship between job insecurity and organizational citizenship behavior among the Eastern Cape Department of Health employees, in Eastern Cape Province of South Africa. The study adopted an exploratory and correlational research design to understand the relationships that exist between the study variables. Respondents were selected using convenience sampling technique, where a sample size of 357 respondents was selected from sample frame of 4847 employees. Seven-point and Five-point likert scale were used to measure the responses. The data analysis methods used include descriptive statistics, regression analysis, ANOVA and Structural Equation Modeling. The reliability, factor analysis and research hypotheses of the research instruments were tested using the aforementioned statistical techniques. The findings reveal a significant negative correlation between job insecurity and Organizational Citizenship Behaviour, a significant positive correlation between psychological empowerment and OCB. It also revealed that job insecurity and psychological empowerment combined account for a significant higher proportion of variance in OCB than any of the two separately, and that significantly and positively moderates the relationship between job insecurity and OCB. Recommendations to promote psychological empowerment in the organization in order to increase organizational citizenship behavior and decrease job insecurity among employees were suggested to leadership of the government departments, organizations and practicing managers.
- Full Text:
- Date Issued: 2019
Characterization of the heat source of thermal aquifers within the Soutpansberg Basin in the Limpopo Province, South Africa: Evidence from geophysical and geological investigations
- Authors: Nyabeze, Peter Kushara
- Date: 2019
- Subjects: Basins (Geology) -- Analysis Geology, Structural -- South Africa
- Language: English
- Type: Thesis , Doctoral , PhD (Geology)
- Identifier: http://hdl.handle.net/10353/15167 , vital:40192
- Description: The research was conducted to contribute towards the knowledge base on the potential for geothermal energy in the Soutpansberg Basin, located in the Limpopo Province of South Africa. The focus area was Siloam, an area that hosts a hottest spring with the highest recorded temperature of 67.5°C. The research involved visits to the Soutpansberg Basin, water sampling, carrying out ground geophysical surveys, and high-level processing of airborne magnetic data to determine depths and temperatures of magnetic sources. The water samples from the hot springs were found to be enriched in sodium, bicarbonate and chlorine with very low concentrations of other element species. The chemical composition of the spring water indicated a source chemistry comprising of the Na-ClHCO3 water assemblage that is a typical signature for deep circulating groundwater of meteoric origin. The circulation depth was inferred to be 2.0 km. The increased resolution of the ground magnetic, electrical resistivity tomography, and electromagnetic conductivity methods data made it possible to delineate subsurface structures at the spring such as dykes, sills, faults and fractures from generated depth models. Modelling of ground magnetic data showed that the Siloam hot spring occurred between two interpreted north dipping dykes approximately 150 m apart. The minimum depth extent of the dykes was interpreted to be 650 m. The magnetic susceptibility values determined from rock measurements and modelling of magnetic data indicated the presence of volcanic and metamorphic rocks. Electromagnetic profiling data showed that there were three main high conductivity zones in the study area with values above 100 mS/m; A central zone associated with the spring; A zone to the south of the spring and a north zone associated with the Siloam Fault. Ground geophysics survey results confirmed the existence of the Siloam Fault. Two artesian boreholes with water warmer than 40 °C were identified to the south of the Siloam hot spring. Both electromagnetic conductivity and electrical resistivity tomography surveys delineated lateral and vertical variation in the bedrock to depths of 40 m to 60 m. Water bearing structures that could be faults, or fractures were identified. Layering due to weathering and water content was found to be in the depth range of 20 m to 40 m. The depths of the potential heat sources were computed from the radially averaged power spectrum of airborne magnetic data for square blocks with side dimensions L of 51 km, 103 km, and 129 km. Spectral analysis based approaches namely Centroid method, Spectral peak method, and the Fractal based approach were used for computing depth and temperatures to heat sources. Airborne magnetic data sets with larger window sizes were preferred for depth computations, as they preserved spectral signatures of deeper sources and reduced the contribution of shallower sources. The size of the data windows did not have a marked effect of depth and temperature values. Shallower magnetic sources depths of approximately 2.0 km were delineated using the Euler deconvolution method. An anticlinal feature at depths of 2.0 to 4.5 km was 4 Final Submission of Thesis, Dissertation or Research Report/Project, Conference or Exam Paper delineated in the central part of the basin. Spectral analysis results indicated that the depth to the top of magnetic sources was at 3.5 km to 6.2 km; the centroid of the basement at 7.92 km to 13.41 km, and the basal below 11.09 km and 14.08 km. The lower end depth spectrum was determined from application of the Centroid method with the deeper being results from the Fractal based approach. The Spectral peak method was useful for determining the depth to the top of magnetic sources. The temperature of the top of magnetic sources and basement centroid were computed to be in the range 234.00 °C to 281.34 °C. Magnetic source depths and basal temperatures that were in the Curie point range within which rocks lose magnetism due to heat were determined, using a computation approach that utilised fractal parameters, to be 21.39 km and 577.42 °C, respectively. Increasing the value of the fractal parameter β from 0 to 4, had an effect of retaining deeper depths and higher temperatures. The fractal parameter β range of 3 to 4 that gave the Curie point parameters indicated basal rock types with an igneous predisposition. The research highlighted evidence for the existence of the Soutpansberg Basin Geothermal Field (SBGF). The area around Siloam is a potential target for drilling exploration geothermal energy boreholes based on the occurrence of hot springs, shallow heat source depths, anticlinal structure, high formation temperatures, deep circulating water and the achieved Curie point temperature.
- Full Text:
- Date Issued: 2019
- Authors: Nyabeze, Peter Kushara
- Date: 2019
- Subjects: Basins (Geology) -- Analysis Geology, Structural -- South Africa
- Language: English
- Type: Thesis , Doctoral , PhD (Geology)
- Identifier: http://hdl.handle.net/10353/15167 , vital:40192
- Description: The research was conducted to contribute towards the knowledge base on the potential for geothermal energy in the Soutpansberg Basin, located in the Limpopo Province of South Africa. The focus area was Siloam, an area that hosts a hottest spring with the highest recorded temperature of 67.5°C. The research involved visits to the Soutpansberg Basin, water sampling, carrying out ground geophysical surveys, and high-level processing of airborne magnetic data to determine depths and temperatures of magnetic sources. The water samples from the hot springs were found to be enriched in sodium, bicarbonate and chlorine with very low concentrations of other element species. The chemical composition of the spring water indicated a source chemistry comprising of the Na-ClHCO3 water assemblage that is a typical signature for deep circulating groundwater of meteoric origin. The circulation depth was inferred to be 2.0 km. The increased resolution of the ground magnetic, electrical resistivity tomography, and electromagnetic conductivity methods data made it possible to delineate subsurface structures at the spring such as dykes, sills, faults and fractures from generated depth models. Modelling of ground magnetic data showed that the Siloam hot spring occurred between two interpreted north dipping dykes approximately 150 m apart. The minimum depth extent of the dykes was interpreted to be 650 m. The magnetic susceptibility values determined from rock measurements and modelling of magnetic data indicated the presence of volcanic and metamorphic rocks. Electromagnetic profiling data showed that there were three main high conductivity zones in the study area with values above 100 mS/m; A central zone associated with the spring; A zone to the south of the spring and a north zone associated with the Siloam Fault. Ground geophysics survey results confirmed the existence of the Siloam Fault. Two artesian boreholes with water warmer than 40 °C were identified to the south of the Siloam hot spring. Both electromagnetic conductivity and electrical resistivity tomography surveys delineated lateral and vertical variation in the bedrock to depths of 40 m to 60 m. Water bearing structures that could be faults, or fractures were identified. Layering due to weathering and water content was found to be in the depth range of 20 m to 40 m. The depths of the potential heat sources were computed from the radially averaged power spectrum of airborne magnetic data for square blocks with side dimensions L of 51 km, 103 km, and 129 km. Spectral analysis based approaches namely Centroid method, Spectral peak method, and the Fractal based approach were used for computing depth and temperatures to heat sources. Airborne magnetic data sets with larger window sizes were preferred for depth computations, as they preserved spectral signatures of deeper sources and reduced the contribution of shallower sources. The size of the data windows did not have a marked effect of depth and temperature values. Shallower magnetic sources depths of approximately 2.0 km were delineated using the Euler deconvolution method. An anticlinal feature at depths of 2.0 to 4.5 km was 4 Final Submission of Thesis, Dissertation or Research Report/Project, Conference or Exam Paper delineated in the central part of the basin. Spectral analysis results indicated that the depth to the top of magnetic sources was at 3.5 km to 6.2 km; the centroid of the basement at 7.92 km to 13.41 km, and the basal below 11.09 km and 14.08 km. The lower end depth spectrum was determined from application of the Centroid method with the deeper being results from the Fractal based approach. The Spectral peak method was useful for determining the depth to the top of magnetic sources. The temperature of the top of magnetic sources and basement centroid were computed to be in the range 234.00 °C to 281.34 °C. Magnetic source depths and basal temperatures that were in the Curie point range within which rocks lose magnetism due to heat were determined, using a computation approach that utilised fractal parameters, to be 21.39 km and 577.42 °C, respectively. Increasing the value of the fractal parameter β from 0 to 4, had an effect of retaining deeper depths and higher temperatures. The fractal parameter β range of 3 to 4 that gave the Curie point parameters indicated basal rock types with an igneous predisposition. The research highlighted evidence for the existence of the Soutpansberg Basin Geothermal Field (SBGF). The area around Siloam is a potential target for drilling exploration geothermal energy boreholes based on the occurrence of hot springs, shallow heat source depths, anticlinal structure, high formation temperatures, deep circulating water and the achieved Curie point temperature.
- Full Text:
- Date Issued: 2019
The anti-proliferative activity of drimia altissima and a novel isolated flavonoid glycoside against hela cervical cancer cells
- Authors: Nyambe, Mutenta Nsokolo
- Date: 2019
- Subjects: Cancer -- Research , Cervix uteri -- Cancer , Cervix uteri -- Cancer -- Diagnosis -- Developing countries
- Language: English
- Type: Thesis , Doctoral , DPhil
- Identifier: http://hdl.handle.net/10948/42770 , vital:36690
- Description: Cancer is one of the leading causes of mortality worldwide. About 44% of all cancer morbidity and 53% of all cancer mortality occur in countries with a low to medium Human Development Index (HDI). Thus, cancer is rapidly emerging as a serious threat to public health in Africa and most especially, sub-Saharan Africa. The International Agency for Research on Cancer (IARC) projects that there will be 1.28 million new cancer cases and 970 000 cancer deaths in Africa by the year 2030 owing to the increase in economic development associated lifestyles. The dominant types of cancer in Africa are those related to infectious diseases such as Kaposi’s sarcoma and cervical, hepatic and urinary bladder carcinomas. The main challenge to cancer treatment in Africa is the unavailability of efficacious anticancer drugs. This is because most developing countries can only afford to procure the most basic anticancer drugs, which are also frequently unavailable due to intermittent supplies. This results in patients progressing to more advanced cancer states. One way of combating this African problem is to focus on research that aims at discovering efficacious and cost effective cancer therapies from available natural resources within the African continent. This study investigated the potential anti-proliferative activity (against HeLa cervical cancer cells) of four plants (Adansonia digitata, Ceiba pentandra, Maytenus senegalensis and Drimia altissima) commonly used in the African traditional treatment of malignancies. After in vitro bio-assay screening using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay, M. senegalensis root extract (MS-R) and D. altissima bulb extract (DA-B) showed anti-proliferative activity against HeLa cervical cancer cells with IC50 values of 25 μg/mL and 1.1 μg/mL respectively. By possessing the strongest anti-proliferative activity among the tested extracts, D. altissima was selected for further studies. Liquid-liquid partitioning of the Drimia altissima bulb extract with n-hexane, ethyl acetate, and n-butanol, yielded partitions 79a – d, with the n-butanol fraction, 79d, exhibiting the strongest cytotoxic activity (IC50 = 0.497 μg/mL). Through High Content Analysis (HCA) screening, fraction 79d was found to induce marked early mitotic cell cycle arrest. Fractionation of 79d using Diaion® HP-20 open column chromatography and a stepwise gradient of reducing polarity (water-methanol-ethanol-ethyl acetate) yielded cytotoxic fractions 82b, 82c, 82d and 82e, all with significant anti-proliferative activities at the tested concentrations of 0.1, 1.0 and 10 μg/mL. Bio-assay guided fractionation of 82c (the most effective fraction at the lowest tested concentration of 0.1 μg/mL) using Sephadex® LH-20 open column chromatography and 50% MeOH led to the isolation of compound 3.17. After structural elucidation using 1D and 2D Nuclear Magnetic Resonance spectroscopy (NMR), High resolution Mass spectrometry (HRMS), Fourier-Transform Infrared spectroscopy (FT-IR), ultraviolet spectroscopy (UV) and Circular Dichroism (CD), compound 3.17 was identified as a novel C-glucosylflavonoid-O-glucoside, 6-C-[-apio-α-D-furanosyl-(1→6)-β-glucopyranosyl]-4′, 5, 7-trihydroxyflavone (Altissimin, 3.17). Compound 3.17 exhibited a dose dependant anti-proliferative activity with an IC50 of 2.44 μM. The mechanism of action for compound 3.17 was investigated through cell cycle arrest, phosphatidylserine translocation (PS), caspase activation and mitochondrial membrane depolarization. The mechanism of cell death elicited by compound 3.17 in HeLa cells was found to involve the induction of M phase cell cycle arrest with consequent activation of apoptotic cell death which was evident from annexin V staining, mitochondrial membrane potential (ΔΨm) collapse and the activation of caspases -8 and -3. In silico computational techniques were employed to virtually determine potential biological targets of compound 3.17. Target fishing using the Similarity Ensemble Approach (SEA) target prediction gave human aldose reductase (hAR, AKR1B1) the highest ranking with a p value of 2.85 x 10-24, a max Tc of 0.35 and a Z-score of 41.8217. Using AutoDock4 and the AutoDock tools suite (ADT), molecular docking of compound 3.17 in the hAR binding pocket was successfully achieved with a lower ΔG free energy binding (-9.4 kcal/mol) than that of positive control ligand 393 (-8.7 kcal/mol). In conclusion, this study identified the genus Drimia and particularly D. altissima as a potential source for novel cytotoxic compounds. The discovery of altissimin (3.17), the first flavonoid glycoside to be isolate from D. altissima, enquires into the possible existence of similar compounds within the species. In addition to the observed in vitro cytotoxic activity against HeLa cells, the potential of altissimin (3.17) as a hAR enzyme inhibitor opens up the possibility of its use as an adjunct to increase cancer cell sensitivity to chemotherapy. Thus, altissimin (3.17) shows promise as a potential anticancer agent.
- Full Text:
- Date Issued: 2019
- Authors: Nyambe, Mutenta Nsokolo
- Date: 2019
- Subjects: Cancer -- Research , Cervix uteri -- Cancer , Cervix uteri -- Cancer -- Diagnosis -- Developing countries
- Language: English
- Type: Thesis , Doctoral , DPhil
- Identifier: http://hdl.handle.net/10948/42770 , vital:36690
- Description: Cancer is one of the leading causes of mortality worldwide. About 44% of all cancer morbidity and 53% of all cancer mortality occur in countries with a low to medium Human Development Index (HDI). Thus, cancer is rapidly emerging as a serious threat to public health in Africa and most especially, sub-Saharan Africa. The International Agency for Research on Cancer (IARC) projects that there will be 1.28 million new cancer cases and 970 000 cancer deaths in Africa by the year 2030 owing to the increase in economic development associated lifestyles. The dominant types of cancer in Africa are those related to infectious diseases such as Kaposi’s sarcoma and cervical, hepatic and urinary bladder carcinomas. The main challenge to cancer treatment in Africa is the unavailability of efficacious anticancer drugs. This is because most developing countries can only afford to procure the most basic anticancer drugs, which are also frequently unavailable due to intermittent supplies. This results in patients progressing to more advanced cancer states. One way of combating this African problem is to focus on research that aims at discovering efficacious and cost effective cancer therapies from available natural resources within the African continent. This study investigated the potential anti-proliferative activity (against HeLa cervical cancer cells) of four plants (Adansonia digitata, Ceiba pentandra, Maytenus senegalensis and Drimia altissima) commonly used in the African traditional treatment of malignancies. After in vitro bio-assay screening using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay, M. senegalensis root extract (MS-R) and D. altissima bulb extract (DA-B) showed anti-proliferative activity against HeLa cervical cancer cells with IC50 values of 25 μg/mL and 1.1 μg/mL respectively. By possessing the strongest anti-proliferative activity among the tested extracts, D. altissima was selected for further studies. Liquid-liquid partitioning of the Drimia altissima bulb extract with n-hexane, ethyl acetate, and n-butanol, yielded partitions 79a – d, with the n-butanol fraction, 79d, exhibiting the strongest cytotoxic activity (IC50 = 0.497 μg/mL). Through High Content Analysis (HCA) screening, fraction 79d was found to induce marked early mitotic cell cycle arrest. Fractionation of 79d using Diaion® HP-20 open column chromatography and a stepwise gradient of reducing polarity (water-methanol-ethanol-ethyl acetate) yielded cytotoxic fractions 82b, 82c, 82d and 82e, all with significant anti-proliferative activities at the tested concentrations of 0.1, 1.0 and 10 μg/mL. Bio-assay guided fractionation of 82c (the most effective fraction at the lowest tested concentration of 0.1 μg/mL) using Sephadex® LH-20 open column chromatography and 50% MeOH led to the isolation of compound 3.17. After structural elucidation using 1D and 2D Nuclear Magnetic Resonance spectroscopy (NMR), High resolution Mass spectrometry (HRMS), Fourier-Transform Infrared spectroscopy (FT-IR), ultraviolet spectroscopy (UV) and Circular Dichroism (CD), compound 3.17 was identified as a novel C-glucosylflavonoid-O-glucoside, 6-C-[-apio-α-D-furanosyl-(1→6)-β-glucopyranosyl]-4′, 5, 7-trihydroxyflavone (Altissimin, 3.17). Compound 3.17 exhibited a dose dependant anti-proliferative activity with an IC50 of 2.44 μM. The mechanism of action for compound 3.17 was investigated through cell cycle arrest, phosphatidylserine translocation (PS), caspase activation and mitochondrial membrane depolarization. The mechanism of cell death elicited by compound 3.17 in HeLa cells was found to involve the induction of M phase cell cycle arrest with consequent activation of apoptotic cell death which was evident from annexin V staining, mitochondrial membrane potential (ΔΨm) collapse and the activation of caspases -8 and -3. In silico computational techniques were employed to virtually determine potential biological targets of compound 3.17. Target fishing using the Similarity Ensemble Approach (SEA) target prediction gave human aldose reductase (hAR, AKR1B1) the highest ranking with a p value of 2.85 x 10-24, a max Tc of 0.35 and a Z-score of 41.8217. Using AutoDock4 and the AutoDock tools suite (ADT), molecular docking of compound 3.17 in the hAR binding pocket was successfully achieved with a lower ΔG free energy binding (-9.4 kcal/mol) than that of positive control ligand 393 (-8.7 kcal/mol). In conclusion, this study identified the genus Drimia and particularly D. altissima as a potential source for novel cytotoxic compounds. The discovery of altissimin (3.17), the first flavonoid glycoside to be isolate from D. altissima, enquires into the possible existence of similar compounds within the species. In addition to the observed in vitro cytotoxic activity against HeLa cells, the potential of altissimin (3.17) as a hAR enzyme inhibitor opens up the possibility of its use as an adjunct to increase cancer cell sensitivity to chemotherapy. Thus, altissimin (3.17) shows promise as a potential anticancer agent.
- Full Text:
- Date Issued: 2019
Indigenous cereal crops and food security issues in Zimbabwe: the case of Matabeleland Provinces
- Authors: Nyathi, Vuyiswa Sandra
- Date: 2019
- Subjects: Food security Farms, Small
- Language: English
- Type: Thesis , Doctoral , PhD (Developmental Studies)
- Identifier: http://hdl.handle.net/10353/17070 , vital:40845
- Description: The study endeavoured to find out how indigenous cereal crops in the form of sorghum, pearl millet and finger millet, popularly known as small grain, would help in increasing cereal production in the dry regions of Zimbabwe so as to alleviate food insecurity. For the past decade the nation’s cereal production has been on the decline with the country having to rely on grain imports from neighbouring countries to prevent hunger. Studies that have been carried out have indicated that these indigenous cereal crops are better suited for semi-arid regions like Matabeleland, used as a case study, where maize has almost always been a failing crop. The study examined representations of smallholder farmers through interviews held with agricultural personnel in Matabeleland North and Matabeleland South Provinces. The study argues that instead of relying on maize only as a staple crop, in the semiarid regions of the country, indigenous cereal crops are suitable alternative staple crops in Zimbabwe. Indications from the findings of the study are that diversification of staple crop production should stress the importance of state mediation, distribution and promotion of indigenous cereal crops. The researcher thus proposes that the reliance on indigenous crops be anchored in community food security, food sovereignty and rural food system perspectives, not negating the negative effects of climate change on food production. The results showed that despite progress made by the state in assisting farmers with agricultural inputs, very little has been achieved in alleviating food insecurity in the dry regions, as indigenous cereal crops continue being pushed to the periphery of the agricultural sector. iii The study concludes by putting forward that addressing the stated challenges could lead to the potential of indigenous cerealcrops potentially increasing the cereal supply for the nation, thus alleviating food security woes as these crops grow favourably even in the most adverse weather conditions and poor topography.
- Full Text:
- Date Issued: 2019
- Authors: Nyathi, Vuyiswa Sandra
- Date: 2019
- Subjects: Food security Farms, Small
- Language: English
- Type: Thesis , Doctoral , PhD (Developmental Studies)
- Identifier: http://hdl.handle.net/10353/17070 , vital:40845
- Description: The study endeavoured to find out how indigenous cereal crops in the form of sorghum, pearl millet and finger millet, popularly known as small grain, would help in increasing cereal production in the dry regions of Zimbabwe so as to alleviate food insecurity. For the past decade the nation’s cereal production has been on the decline with the country having to rely on grain imports from neighbouring countries to prevent hunger. Studies that have been carried out have indicated that these indigenous cereal crops are better suited for semi-arid regions like Matabeleland, used as a case study, where maize has almost always been a failing crop. The study examined representations of smallholder farmers through interviews held with agricultural personnel in Matabeleland North and Matabeleland South Provinces. The study argues that instead of relying on maize only as a staple crop, in the semiarid regions of the country, indigenous cereal crops are suitable alternative staple crops in Zimbabwe. Indications from the findings of the study are that diversification of staple crop production should stress the importance of state mediation, distribution and promotion of indigenous cereal crops. The researcher thus proposes that the reliance on indigenous crops be anchored in community food security, food sovereignty and rural food system perspectives, not negating the negative effects of climate change on food production. The results showed that despite progress made by the state in assisting farmers with agricultural inputs, very little has been achieved in alleviating food insecurity in the dry regions, as indigenous cereal crops continue being pushed to the periphery of the agricultural sector. iii The study concludes by putting forward that addressing the stated challenges could lead to the potential of indigenous cerealcrops potentially increasing the cereal supply for the nation, thus alleviating food security woes as these crops grow favourably even in the most adverse weather conditions and poor topography.
- Full Text:
- Date Issued: 2019
Examination of teacher mediation and its impact on foundational reading skills in Grade-R classrooms in Namibia
- Authors: Nzwala, Kenneth
- Date: 2019
- Subjects: Reading (Elementary) -- Namibia -- Case studies , Elementary school teachers -- Namibia -- Case studies , Early childhood education -- Curricula -- Namibia , Vygotskiĭ, L. S. (Lev Semenovich), 1896-1934
- Language: English
- Type: text , Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/92291 , vital:30700
- Description: Grounded in the Sociocultural Theory (SCT) of Lev Vygotsky, this study examined teacher mediation and its impact on development of foundational reading skills in six Grade-R classrooms in the Zambezi Region of Namibia. It was a multiple case study with a mixed methods approach. Six Grade R classes attached to primary schools were studied to facilitate following of the same learners to Grade One. A purposive sampling technique was used to draw a sample of six Grade-R and Grade-One teachers. Learners were selected using stratified random sampling. Data were collected by means of interviews, observation of Grade R lessons, and an emergent Early Grade Reading Assessment (eEGRA) test. eEGRA facilitated benchmarking teacher efficacy in mediating Grade R learners’ foundational reading skills. Nine Grade One learners per teacher per school took part in the test at the beginning of Grade One. Three 35-minute lessons, per Grade-R teacher, were observed. Data were analysed statistically using ANOVA with thematic qualitative analysis of interview data against document analysis of curricula, teacher planning and learner exercise books. The study established that teachers had no understanding of ‘emergent literacy’, did not promote a love of books, or promote learning through play. There was evidence of a language barrier during lessons, which potentially reduced the efficacy of teacher mediation. The curriculum was found to be inappropriate as it lacked guidance relevant to Grade R teachers. This point was particularly pertinent as all teachers in this study had not received Grade-R training and were therefore looking to the curriculum for support. The difference between what teachers said and what they did was revealed in their classroom practice. Lesson planning was found to be superficial and non-reflective, with a marked discrepancy between what was planned and what was done. The style of pedagogy was primarily transmissive and authoritarian. Finally, the socio-economic distribution of the schools did not demonstrate significant impact on learner performance in the benchmark test. This study concludes that the Grade-R curriculum needs to be revised to be culturally and age appropriate. Teachers should be trained to understand the speciality of Grade R, and support should be given to current teachers to adopt a child-centred, play-based approach to pedagogy.
- Full Text:
- Date Issued: 2019
- Authors: Nzwala, Kenneth
- Date: 2019
- Subjects: Reading (Elementary) -- Namibia -- Case studies , Elementary school teachers -- Namibia -- Case studies , Early childhood education -- Curricula -- Namibia , Vygotskiĭ, L. S. (Lev Semenovich), 1896-1934
- Language: English
- Type: text , Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/92291 , vital:30700
- Description: Grounded in the Sociocultural Theory (SCT) of Lev Vygotsky, this study examined teacher mediation and its impact on development of foundational reading skills in six Grade-R classrooms in the Zambezi Region of Namibia. It was a multiple case study with a mixed methods approach. Six Grade R classes attached to primary schools were studied to facilitate following of the same learners to Grade One. A purposive sampling technique was used to draw a sample of six Grade-R and Grade-One teachers. Learners were selected using stratified random sampling. Data were collected by means of interviews, observation of Grade R lessons, and an emergent Early Grade Reading Assessment (eEGRA) test. eEGRA facilitated benchmarking teacher efficacy in mediating Grade R learners’ foundational reading skills. Nine Grade One learners per teacher per school took part in the test at the beginning of Grade One. Three 35-minute lessons, per Grade-R teacher, were observed. Data were analysed statistically using ANOVA with thematic qualitative analysis of interview data against document analysis of curricula, teacher planning and learner exercise books. The study established that teachers had no understanding of ‘emergent literacy’, did not promote a love of books, or promote learning through play. There was evidence of a language barrier during lessons, which potentially reduced the efficacy of teacher mediation. The curriculum was found to be inappropriate as it lacked guidance relevant to Grade R teachers. This point was particularly pertinent as all teachers in this study had not received Grade-R training and were therefore looking to the curriculum for support. The difference between what teachers said and what they did was revealed in their classroom practice. Lesson planning was found to be superficial and non-reflective, with a marked discrepancy between what was planned and what was done. The style of pedagogy was primarily transmissive and authoritarian. Finally, the socio-economic distribution of the schools did not demonstrate significant impact on learner performance in the benchmark test. This study concludes that the Grade-R curriculum needs to be revised to be culturally and age appropriate. Teachers should be trained to understand the speciality of Grade R, and support should be given to current teachers to adopt a child-centred, play-based approach to pedagogy.
- Full Text:
- Date Issued: 2019
Synthesis, characterisation and biological evaluation of novel anti-infective compounds bearing ferrocene, arylpyrrole, thiazolidinedione, quinoline and triazole moieties
- Authors: Oderinlo, Ogunyemi Olajide
- Date: 2019
- Language: English
- Type: text , Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/114714 , vital:34016 , 10.21504/10962/114714
- Description: Expected release date-April 2022
- Full Text: false
- Date Issued: 2019
- Authors: Oderinlo, Ogunyemi Olajide
- Date: 2019
- Language: English
- Type: text , Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/114714 , vital:34016 , 10.21504/10962/114714
- Description: Expected release date-April 2022
- Full Text: false
- Date Issued: 2019
Application of some missing data techniques in estimating missing data in high blood pressure covariates
- Authors: Odeyemi, A. S
- Date: 2019
- Subjects: Missing observations (Statistics) Hypertension
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10353/15189 , vital:40195
- Description: Cases recorded with high blood pressure are a major concern in both public and private hospitals. Adequate provision of health information of patients relating to high blood pressure in Eastern Cape Hospitals hinges so much on the outcome of statistical analysis results. The usual statistical methodologies become inadequate in handling statistical analysis of data collected due to incomplete patients’ information stored in the hospital database. From time to time, new methods are developed to address the problem of missing data. High blood pressure is linked to a lot of diseases such hypertension, cardiovascular disease, kidney disease and stroke. In this study, we developed a new method for addressing the problem of missing data in assessing model used for estimating missing values in terms of minimum errors(using RMSE, MAE, and SE) and goodness-of-fits(using 2 R and adjusted 2 R ) of this model and P-value. . The study compared six different methods: Original data (OD), Listwise deletion (LD), Mean imputations (MEI), Mean above (MA), and Mean above below(MAB) and two steps nearest neighbour (2-NN).The comparison was performed using original data set, and missing values at 5%, 10%, 20%, 30% were simulated on Framingham risk scores under MCAR and MAR simulation on BMI values given some assumptions. Five performance indicators were used to describe the model minimum errors and goodness of fit for all the methods. The results showed that the 2-NN is the best replacement method at lower levels (5% and10%) of missing values while MA and MEI performed best at higher levels(15% and 20%) of missing values. All comparison was based on estimates closest to those of the original data where no value was missing. MAR results showed that 2-NN performed better than LD,MA,MAB, and MEI at 5%,10%, and 20% levels of missing data in terms of absolute difference in p-value to original data.
- Full Text:
- Date Issued: 2019
- Authors: Odeyemi, A. S
- Date: 2019
- Subjects: Missing observations (Statistics) Hypertension
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10353/15189 , vital:40195
- Description: Cases recorded with high blood pressure are a major concern in both public and private hospitals. Adequate provision of health information of patients relating to high blood pressure in Eastern Cape Hospitals hinges so much on the outcome of statistical analysis results. The usual statistical methodologies become inadequate in handling statistical analysis of data collected due to incomplete patients’ information stored in the hospital database. From time to time, new methods are developed to address the problem of missing data. High blood pressure is linked to a lot of diseases such hypertension, cardiovascular disease, kidney disease and stroke. In this study, we developed a new method for addressing the problem of missing data in assessing model used for estimating missing values in terms of minimum errors(using RMSE, MAE, and SE) and goodness-of-fits(using 2 R and adjusted 2 R ) of this model and P-value. . The study compared six different methods: Original data (OD), Listwise deletion (LD), Mean imputations (MEI), Mean above (MA), and Mean above below(MAB) and two steps nearest neighbour (2-NN).The comparison was performed using original data set, and missing values at 5%, 10%, 20%, 30% were simulated on Framingham risk scores under MCAR and MAR simulation on BMI values given some assumptions. Five performance indicators were used to describe the model minimum errors and goodness of fit for all the methods. The results showed that the 2-NN is the best replacement method at lower levels (5% and10%) of missing values while MA and MEI performed best at higher levels(15% and 20%) of missing values. All comparison was based on estimates closest to those of the original data where no value was missing. MAR results showed that 2-NN performed better than LD,MA,MAB, and MEI at 5%,10%, and 20% levels of missing data in terms of absolute difference in p-value to original data.
- Full Text:
- Date Issued: 2019
Communication barriers within virtual communities in an ethnoreligious diverse society: a case study of Nigeria
- Authors: Ogunnubi ,Adeyemi
- Date: 2019
- Subjects: Communication
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10353/15859 , vital:40533
- Description: The study explores the communication barriers that exist within virtual communities in an ethno-religious diverse society like Nigeria. Qualitative research approach was employed. Subsequently, data was collected using qualitative questionnaire that contained open ended questions and through participant observation (online ethnography). Purposive sampling was used to select participants through liaising with Facebook users, as one of the online virtual communities in Nigeria. Having monitored online discourse on Facebook for some months, this study purposively selected 300 active facebook users from various Nigerian cultural and ethnic backgrounds, but only 60 participants indicated their interest to participate. Also, out of the 60 participants who agreed to participate, only 30 participants (25 males and 5 females) fully participated to the final stage while the other 30 withdrew from the study. The participants were mainly adults between the age brackets of 20 and 59. Thematic Analysis was subsequently used to analyse the data by identifying main themes to provide detailed descriptions of the setting, participants as well as activities. The findings of this study revealed that majority of the participants agree that due to Facebook familiarity and Nigeria's religious colouration, there is a display of disrespect, insolence and deep arrogance to other interactants online. The study further identified and revealed other barriers such as differences in cultural backgrounds and opinions, lack of politeness, prejudging and filtering, name calling and insults. The study proposes that social media platforms as virtual communities should be regulated with full implementation of the law and its sustenance, regardless of individuals having power to make their own choices about the kind of languages they use within virtual communities and considering its effect on other online users. Vulgar languages, hate speeches, incitements, bullying and other offensive comments would hopefully be curbed to the barest minimum if this intervention could be implemented. The conclusion of the study was that Nigerians should be civil in responding to discourse in virtual communities as certain inflammatory, religious or utterances based on ethnicity due to an uninformed perspective usually display one's poor knowledge on issues of national interests
- Full Text:
- Date Issued: 2019
- Authors: Ogunnubi ,Adeyemi
- Date: 2019
- Subjects: Communication
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10353/15859 , vital:40533
- Description: The study explores the communication barriers that exist within virtual communities in an ethno-religious diverse society like Nigeria. Qualitative research approach was employed. Subsequently, data was collected using qualitative questionnaire that contained open ended questions and through participant observation (online ethnography). Purposive sampling was used to select participants through liaising with Facebook users, as one of the online virtual communities in Nigeria. Having monitored online discourse on Facebook for some months, this study purposively selected 300 active facebook users from various Nigerian cultural and ethnic backgrounds, but only 60 participants indicated their interest to participate. Also, out of the 60 participants who agreed to participate, only 30 participants (25 males and 5 females) fully participated to the final stage while the other 30 withdrew from the study. The participants were mainly adults between the age brackets of 20 and 59. Thematic Analysis was subsequently used to analyse the data by identifying main themes to provide detailed descriptions of the setting, participants as well as activities. The findings of this study revealed that majority of the participants agree that due to Facebook familiarity and Nigeria's religious colouration, there is a display of disrespect, insolence and deep arrogance to other interactants online. The study further identified and revealed other barriers such as differences in cultural backgrounds and opinions, lack of politeness, prejudging and filtering, name calling and insults. The study proposes that social media platforms as virtual communities should be regulated with full implementation of the law and its sustenance, regardless of individuals having power to make their own choices about the kind of languages they use within virtual communities and considering its effect on other online users. Vulgar languages, hate speeches, incitements, bullying and other offensive comments would hopefully be curbed to the barest minimum if this intervention could be implemented. The conclusion of the study was that Nigerians should be civil in responding to discourse in virtual communities as certain inflammatory, religious or utterances based on ethnicity due to an uninformed perspective usually display one's poor knowledge on issues of national interests
- Full Text:
- Date Issued: 2019
An assessment of school food and nutrition environments for strengthening the integrated school health policy in the Eastern Cape, South Africa
- Authors: Okeyo, Alice Phelgona
- Date: 2019
- Subjects: Nutrition policy -- South Africa -- Eastern Cape School health services -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Doctoral , DPhil
- Identifier: http://hdl.handle.net/10353/17039 , vital:40836
- Description: The 2012 Integrated School Health Policy (ISHP) offers a framework for adequate school food environment. It aims to contribute to the improvement of the general health of school-going children and to address health barriers to learning in order to improve education outcomes. This study assessed the school food and nutrition environment and critically appraised the position of nutrition within ISHP in order to make recommendations for best practice and promotion of healthy-eating in quintiles 1 – 3 secondary school learners of the Eastern Cape, South Africa. Areas evaluated included the school food environment (National School Food Nutrition Programme, NSNP, tuck-shop, vendor, lunch box, and school vegetable garden); eating practice; nutrition knowledge; and nutrition status. A quantitative and qualitative cross-sectional design was applied in data collection. Data was collected from 1,357 learners at 18 secondary schools in three districts: Buffalo City Metropolitan Municipality, Chris Hani and OR Tambo, using semi-structured questionnaires. Five major food items provided in the school food and nutrition environment included: beans, pap, sour-milk, rice, and samp (maize) (NSNP); chips, sandwich, pap, biscuits, and cake (tuck-shop); chips, sandwich, pap, cake, and pop-corn (vendor); and samp (maize), noodles, fat-cake, chips, and Russian/Viennas (lunch boxes). Only three of the 16 schools had school vegetable gardens which produced vegetables and no fruits. Five most frequently eaten foods for breakfast were porridge, rusks, stiff-pap, bread-with-spread, eggs, and polony. Learners from quintile 3 (60.8percent) significantly ate more cooked porridge than learners from quintiles 1 and 2 (51.9percent) (p = 0.015). Leaners from quintile 3 (59.4percent) significantly ate more brown bread-with-spread than learners from quintiles 1 and 2 (50.4) (p = 0.022). The majority of learners (72.7percent) ate breakfast; more male learners (24.4percent) than female learners (29.1percent) skipped breakfast. The majority (62.2percent) of learners had poor nutritional knowledge; significantly, more male (35percent) than female (27percent) learners had poor nutritional knowledge (p = 0.003). Nutritional knowledge increased with age; significantly more grade 8 learners had poor (42.6percent) nutritional knowledge than grade 12 learners (14.1percent) (p < 0.001). Leaners from quintile 3 had good (23.5percent) nutritional knowledge than learners from quintiles 1 and 2 (15.7percent) (p < 0.001). School lessons, books and television were the most important source for nutritional information to learners. The most significant source was lessons (72.0percent; p < 0.001); followed by television (69.4percent; p < 0.001) and books (67.8percent; p = 0.014), in that ranking order. The majority of learners (64percent) had normal body weight. The prevalence of underweight, overweight and obesity was 13.0percent, 15.0percent and 8.0percent, respectively. The prevalence of overweight and obesity was higher in females than males (21.3percent vs 5.3percent; overweight; p < 0.001)) and (11.6percent vs 1.2percent; obesity; p < 0.001), respectively; while the prevalence in terms of underweight was significantly higher in male (21.3percent) learners than in female learners (8.1percent); p < 0.001. The study indicated that the school food environment was not supported by ISHP. The Integrated School Health Policy did not include on-site package for nutritional assessment, thus, there is need to offer nutritional interventions in schools.
- Full Text:
- Date Issued: 2019
- Authors: Okeyo, Alice Phelgona
- Date: 2019
- Subjects: Nutrition policy -- South Africa -- Eastern Cape School health services -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Doctoral , DPhil
- Identifier: http://hdl.handle.net/10353/17039 , vital:40836
- Description: The 2012 Integrated School Health Policy (ISHP) offers a framework for adequate school food environment. It aims to contribute to the improvement of the general health of school-going children and to address health barriers to learning in order to improve education outcomes. This study assessed the school food and nutrition environment and critically appraised the position of nutrition within ISHP in order to make recommendations for best practice and promotion of healthy-eating in quintiles 1 – 3 secondary school learners of the Eastern Cape, South Africa. Areas evaluated included the school food environment (National School Food Nutrition Programme, NSNP, tuck-shop, vendor, lunch box, and school vegetable garden); eating practice; nutrition knowledge; and nutrition status. A quantitative and qualitative cross-sectional design was applied in data collection. Data was collected from 1,357 learners at 18 secondary schools in three districts: Buffalo City Metropolitan Municipality, Chris Hani and OR Tambo, using semi-structured questionnaires. Five major food items provided in the school food and nutrition environment included: beans, pap, sour-milk, rice, and samp (maize) (NSNP); chips, sandwich, pap, biscuits, and cake (tuck-shop); chips, sandwich, pap, cake, and pop-corn (vendor); and samp (maize), noodles, fat-cake, chips, and Russian/Viennas (lunch boxes). Only three of the 16 schools had school vegetable gardens which produced vegetables and no fruits. Five most frequently eaten foods for breakfast were porridge, rusks, stiff-pap, bread-with-spread, eggs, and polony. Learners from quintile 3 (60.8percent) significantly ate more cooked porridge than learners from quintiles 1 and 2 (51.9percent) (p = 0.015). Leaners from quintile 3 (59.4percent) significantly ate more brown bread-with-spread than learners from quintiles 1 and 2 (50.4) (p = 0.022). The majority of learners (72.7percent) ate breakfast; more male learners (24.4percent) than female learners (29.1percent) skipped breakfast. The majority (62.2percent) of learners had poor nutritional knowledge; significantly, more male (35percent) than female (27percent) learners had poor nutritional knowledge (p = 0.003). Nutritional knowledge increased with age; significantly more grade 8 learners had poor (42.6percent) nutritional knowledge than grade 12 learners (14.1percent) (p < 0.001). Leaners from quintile 3 had good (23.5percent) nutritional knowledge than learners from quintiles 1 and 2 (15.7percent) (p < 0.001). School lessons, books and television were the most important source for nutritional information to learners. The most significant source was lessons (72.0percent; p < 0.001); followed by television (69.4percent; p < 0.001) and books (67.8percent; p = 0.014), in that ranking order. The majority of learners (64percent) had normal body weight. The prevalence of underweight, overweight and obesity was 13.0percent, 15.0percent and 8.0percent, respectively. The prevalence of overweight and obesity was higher in females than males (21.3percent vs 5.3percent; overweight; p < 0.001)) and (11.6percent vs 1.2percent; obesity; p < 0.001), respectively; while the prevalence in terms of underweight was significantly higher in male (21.3percent) learners than in female learners (8.1percent); p < 0.001. The study indicated that the school food environment was not supported by ISHP. The Integrated School Health Policy did not include on-site package for nutritional assessment, thus, there is need to offer nutritional interventions in schools.
- Full Text:
- Date Issued: 2019
Ict literacy skills and demographic factors as determinants of electronic resources use among the undergraduate students in the selected universities the Eastern Cape, South Africa
- Olatoye , Oluwayemi IbukunOluwa
- Authors: Olatoye , Oluwayemi IbukunOluwa
- Date: 2019
- Subjects: Electronic information resources
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10353/16176 , vital:40675
- Description: In today’s world, information is the foundation on which every strata in society is built and established. As we are in the jet age, the use of Information Communications Technology (ICT) is sine-qua-non to academic development. It is equally important to acquire skills and build capacity in ICT applications, as well as reflect on the demographic factors that determine the utilization of electronic resources among the undergraduate respondents. ICT has also evolutionalized professionalism in librarianship by providing delivery of appropriate, suitable and value-added information services in digital format. This research, therefore, investigated undergraduate students’ ICT literacy skills and demographic factors as determinants of electronic resources use, with selected tertiary institutions of learning in Eastern Cape South Africa as a case study. The study was premised on the Diffusion of Innovation Theory (DOI), Technology Acceptance Model (TAM) and the Theory of Reasoned Action (TRA) with the aim of appraising undergraduate students’ ICT literacy skills and demographic factors as causative elements of e-resources utilization in designated Eastern Cape universities in South Africa, as well as to unravel the impact of the theories on the adoption of technology and the perceived utilization of the electronic resources. The application of DOI, TAM and TRA theories for this study exemplifies the acceptance and usage of technological innovations by envisioned users in ICT literacy skill and electronic resources research, and these theories formed the theoretical basis to strengthen the study. The specific x objectives of the study are: To ascertain how undergraduate students in selected Higher Education Institutions (HEIs) in the Eastern Cape access e-resources; to determine the level of influence of ICT literacy skills on the use of electronic resources by Undergraduate students in the selected universities; to determine the regularity levels of use and problems encountered in the use of electronic resources by Undergraduate students in the selected universities; to ascertain the contributions of demographic factors on the use of electronic resources by Undergraduate students in the selected universities; and to determine the attitudes and perceptions of undergraduate students towards the use of eresources. The approach of the study was in threefold; one, general discussion regarding ICT literacy skills of the respondents and secondly the demographic factors that determine electronic resources use of undergraduate students in the University of Fort Hare and Rhodes University. Finally, ICT literacy skills and demographic factors were investigated with the applicability of TAM, DOI and TRA theories Specifically, under these theories (TAM, TRA and DOI), TAM and TRA models were used to explain behavioural intention and to envisage user acceptance of technology usage (electronic resources), and to elucidate the correlation between the respondent’s (undergraduate students) perceptions, attitudes, beliefs and ultimately system utilization. DOI was conceptualized in this study as a valued tool for appraising the effect of demographic factors on the utilization of electronic resources among the undergraduate students in their academic pursuit. The major findings of the study specifies that ICT literacy skills and demographic factors determine the use of electronic resources. Hence, it is reasoned in the thesis that ICT xi literacy and demographic factors affects the frequency of electronic resources with those, for instance, who have obtained high ICT literacy skill levels when compared to others who are yet to develop their ICT literacy skills. Further, it has been disclosed elsewhere in the study that in terms of age, the younger undergraduate students (from 21 to 30 years) utilize electronic resources more regularly than their older colleagues (those who are 30 years of age and above).The study was approached with the adoption of the mixed-method research technique. The administration of a total of 377 copies of the questionnaire to undergraduate respondents in the aforementioned HEIs, (out of which 266 copies were returned), was conducted with in-depth interview conversations comprising of ten participants, with six respondents selected in the University of Fort Hare and four respondents from Rhodes University. Data acquired from the study were processed and analyzed with the aid of Statistical Package for Social Science (SPSS) for the quantitative data. In the light of the theoretical frameworks of the study, research results established that the ICT experience of the undergraduate respondents greatly influences their proficiency levels. This hypothesized assertion was subjected to statistical validity test through regression analysis. The result depicts that the p-value is 0.49 (which means that p≤ 0.05), and interprets to mean that the hypothesis is accepted. Also, the findings of this study depicts that the utilization of electronic resources by the respondents is mostly for entertainment purposes (such as viewing online videos, listening to sport commentaries, music and video downloads, e-mail communications, chatting with other people) had the highest rankings from the component matrix analysis which were greater than 0.5. From the forgoing, this is interpreted to mean that the respondents possess excellent proficiency in ICT literacy skills as well as in the use of Microsoft packages. xii Also, in the course of the in-depth research interview, it was discovered that most of the interviewees have excellent proficiency in ICT literacy skills. Generally, gender is an essential element that determines accessibility and e-resource utilization of respondents to electronic resources through the home and from other sources. Furthermore, it was discovered that that language is not a determinant regarding respondents’ accessibility and e-resource utilization from other sources of access to respondents. The analysis of this study revealed that more males, who are within the active e-resource using age bracket of 21 to 30 years old access and utilize electronic resources through the residences than their female counterparts. This age bracket is followed in terms of access and use of e-resources through residences by the respondents that are 20 years and below. A chi-square test of independence was also performed to survey the level of correlation between age and access to E-resources. A small p-value (typically ≤ 0.05) indicates strong evidence against the null hypothesis, so you reject the null hypothesis. A large p-value (> 0.05) shows weak evidence against the null hypothesis, so you reject the null hypothesis i.e. X2 (3, N=53) = 7.82. The Pearson chi-square (p-value) generated was .294, which is construed to mean that it is insignificant. Therefore, the explanation is that age has no influence on access of respondents to electronic resources through cybercafé. In order to make ICT literacy skills more beneficial to the undergraduate students in the selected HEIs, recommendations were made in this study. Firstly, there is a need for mass enlightenment campaigns on the use and benefits of E-resources among undergraduate respondents, the building of capacity of the undergraduate students in the use of electronic resources ICT literacy skill development programmes, need for intervention programmes focusing on the application xiii of some E-resources and software where the students are ranked low. Further, it is recommended that female students need to be encouraged to use E-resources. Also, delivery and empowering of Wi-Fi services, as well as the provision of CD- ROM databases should be considered.
- Full Text:
- Date Issued: 2019
- Authors: Olatoye , Oluwayemi IbukunOluwa
- Date: 2019
- Subjects: Electronic information resources
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10353/16176 , vital:40675
- Description: In today’s world, information is the foundation on which every strata in society is built and established. As we are in the jet age, the use of Information Communications Technology (ICT) is sine-qua-non to academic development. It is equally important to acquire skills and build capacity in ICT applications, as well as reflect on the demographic factors that determine the utilization of electronic resources among the undergraduate respondents. ICT has also evolutionalized professionalism in librarianship by providing delivery of appropriate, suitable and value-added information services in digital format. This research, therefore, investigated undergraduate students’ ICT literacy skills and demographic factors as determinants of electronic resources use, with selected tertiary institutions of learning in Eastern Cape South Africa as a case study. The study was premised on the Diffusion of Innovation Theory (DOI), Technology Acceptance Model (TAM) and the Theory of Reasoned Action (TRA) with the aim of appraising undergraduate students’ ICT literacy skills and demographic factors as causative elements of e-resources utilization in designated Eastern Cape universities in South Africa, as well as to unravel the impact of the theories on the adoption of technology and the perceived utilization of the electronic resources. The application of DOI, TAM and TRA theories for this study exemplifies the acceptance and usage of technological innovations by envisioned users in ICT literacy skill and electronic resources research, and these theories formed the theoretical basis to strengthen the study. The specific x objectives of the study are: To ascertain how undergraduate students in selected Higher Education Institutions (HEIs) in the Eastern Cape access e-resources; to determine the level of influence of ICT literacy skills on the use of electronic resources by Undergraduate students in the selected universities; to determine the regularity levels of use and problems encountered in the use of electronic resources by Undergraduate students in the selected universities; to ascertain the contributions of demographic factors on the use of electronic resources by Undergraduate students in the selected universities; and to determine the attitudes and perceptions of undergraduate students towards the use of eresources. The approach of the study was in threefold; one, general discussion regarding ICT literacy skills of the respondents and secondly the demographic factors that determine electronic resources use of undergraduate students in the University of Fort Hare and Rhodes University. Finally, ICT literacy skills and demographic factors were investigated with the applicability of TAM, DOI and TRA theories Specifically, under these theories (TAM, TRA and DOI), TAM and TRA models were used to explain behavioural intention and to envisage user acceptance of technology usage (electronic resources), and to elucidate the correlation between the respondent’s (undergraduate students) perceptions, attitudes, beliefs and ultimately system utilization. DOI was conceptualized in this study as a valued tool for appraising the effect of demographic factors on the utilization of electronic resources among the undergraduate students in their academic pursuit. The major findings of the study specifies that ICT literacy skills and demographic factors determine the use of electronic resources. Hence, it is reasoned in the thesis that ICT xi literacy and demographic factors affects the frequency of electronic resources with those, for instance, who have obtained high ICT literacy skill levels when compared to others who are yet to develop their ICT literacy skills. Further, it has been disclosed elsewhere in the study that in terms of age, the younger undergraduate students (from 21 to 30 years) utilize electronic resources more regularly than their older colleagues (those who are 30 years of age and above).The study was approached with the adoption of the mixed-method research technique. The administration of a total of 377 copies of the questionnaire to undergraduate respondents in the aforementioned HEIs, (out of which 266 copies were returned), was conducted with in-depth interview conversations comprising of ten participants, with six respondents selected in the University of Fort Hare and four respondents from Rhodes University. Data acquired from the study were processed and analyzed with the aid of Statistical Package for Social Science (SPSS) for the quantitative data. In the light of the theoretical frameworks of the study, research results established that the ICT experience of the undergraduate respondents greatly influences their proficiency levels. This hypothesized assertion was subjected to statistical validity test through regression analysis. The result depicts that the p-value is 0.49 (which means that p≤ 0.05), and interprets to mean that the hypothesis is accepted. Also, the findings of this study depicts that the utilization of electronic resources by the respondents is mostly for entertainment purposes (such as viewing online videos, listening to sport commentaries, music and video downloads, e-mail communications, chatting with other people) had the highest rankings from the component matrix analysis which were greater than 0.5. From the forgoing, this is interpreted to mean that the respondents possess excellent proficiency in ICT literacy skills as well as in the use of Microsoft packages. xii Also, in the course of the in-depth research interview, it was discovered that most of the interviewees have excellent proficiency in ICT literacy skills. Generally, gender is an essential element that determines accessibility and e-resource utilization of respondents to electronic resources through the home and from other sources. Furthermore, it was discovered that that language is not a determinant regarding respondents’ accessibility and e-resource utilization from other sources of access to respondents. The analysis of this study revealed that more males, who are within the active e-resource using age bracket of 21 to 30 years old access and utilize electronic resources through the residences than their female counterparts. This age bracket is followed in terms of access and use of e-resources through residences by the respondents that are 20 years and below. A chi-square test of independence was also performed to survey the level of correlation between age and access to E-resources. A small p-value (typically ≤ 0.05) indicates strong evidence against the null hypothesis, so you reject the null hypothesis. A large p-value (> 0.05) shows weak evidence against the null hypothesis, so you reject the null hypothesis i.e. X2 (3, N=53) = 7.82. The Pearson chi-square (p-value) generated was .294, which is construed to mean that it is insignificant. Therefore, the explanation is that age has no influence on access of respondents to electronic resources through cybercafé. In order to make ICT literacy skills more beneficial to the undergraduate students in the selected HEIs, recommendations were made in this study. Firstly, there is a need for mass enlightenment campaigns on the use and benefits of E-resources among undergraduate respondents, the building of capacity of the undergraduate students in the use of electronic resources ICT literacy skill development programmes, need for intervention programmes focusing on the application xiii of some E-resources and software where the students are ranked low. Further, it is recommended that female students need to be encouraged to use E-resources. Also, delivery and empowering of Wi-Fi services, as well as the provision of CD- ROM databases should be considered.
- Full Text:
- Date Issued: 2019
Effect of social capital and information acquisition on the adoption and benefits of conservation agriculture among cassava and maize smallholder farmers in South-West Nigeria
- Authors: Olawuyi, Seyi Olalekan
- Date: 2019
- Subjects: Agricultural conservation Sustainable agriculture Farms, Small|
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10353/15200 , vital:40200
- Description: Sustainable economic growth and development in developing economy like Nigeria is achievable through the agricultural sector and sub-sectors which are concentrated in rural areas. Rural areas represent a home to majority (about 75%) of the households practicing farming for family sustenance and/or to earn income from the sales of agricultural products (Oyakhilomen and Zibah, 2014). In addition to the persistent use of traditional farming practices, these rural farming households cultivate crops varieties that are low-yielding on small and scattered farmland holdings (smallholder farmers) (Oyakhilomen and Zibah, 2014). This act depletes the soil organic matter with devastating consequences on production output, income generation as well as the ecosystem. Similarly, non-access to agricultural credit and limited technical knowhow are parts of the challenges that are facing the development of farming activities in subSaharan Africa, including Nigeria (Kassie, Pender, Yesuf, Köhlin, Bluffstone and Mulugeta, 2008). These challenges call for holistic interventions such as conservative agricultural practices; which are sustainable, promote safe environment and ultimately increase production output.
- Full Text:
- Date Issued: 2019
- Authors: Olawuyi, Seyi Olalekan
- Date: 2019
- Subjects: Agricultural conservation Sustainable agriculture Farms, Small|
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10353/15200 , vital:40200
- Description: Sustainable economic growth and development in developing economy like Nigeria is achievable through the agricultural sector and sub-sectors which are concentrated in rural areas. Rural areas represent a home to majority (about 75%) of the households practicing farming for family sustenance and/or to earn income from the sales of agricultural products (Oyakhilomen and Zibah, 2014). In addition to the persistent use of traditional farming practices, these rural farming households cultivate crops varieties that are low-yielding on small and scattered farmland holdings (smallholder farmers) (Oyakhilomen and Zibah, 2014). This act depletes the soil organic matter with devastating consequences on production output, income generation as well as the ecosystem. Similarly, non-access to agricultural credit and limited technical knowhow are parts of the challenges that are facing the development of farming activities in subSaharan Africa, including Nigeria (Kassie, Pender, Yesuf, Köhlin, Bluffstone and Mulugeta, 2008). These challenges call for holistic interventions such as conservative agricultural practices; which are sustainable, promote safe environment and ultimately increase production output.
- Full Text:
- Date Issued: 2019
Nutritional quality of sausage made with edible meat waste and the perception of consumers on offal product in Eastern Cape Province, South Africa
- Authors: Oluwasegun, Babatunde Alao
- Date: 2019
- Subjects: Meat -- Quality
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10353/19021 , vital:40094
- Description: Meat processing at the abattoir provides meat by product and waste while, the major part of the muscle which constitutes a third is edible. The edible by products (EBP) of meat have a notable position in our day-to-day life and are used in diverse forms. However, the quality of offal meat may differ according to intrinsic and extrinsic attributes that may occasionally be shaped by the attitude of consumers towards the products. Therefore, the first objective of this thesis focused on features that might influence consumer preferences and their perception of offal meat. A total of 202 consumers from three Municipalities in Amathole District were randomly sampled using exponential nondiscriminative snowball sampling. Data were gathered through a structured questionnaire containing open ended and closed ended questions. The study showed that consumers were more influenced by the freshness, price and availability of the product and these factors are used to determine the purchase outlet. Differences were observed in the offal meat consumption between the age groups. Age groups 25-34 (29.7%) and 35-44 (27.4%) showed the highest offal meat consumption, while the decline was observed in age groups of 55-64 (11.9%), 65- 74 (5.9%) and 75-85 (0.01%) respectively. The most preferred purchase point for offal meat in this study was in butcheries. However, it was observed that the factors influencing offal consumption in Amathole District were similar to meat consumption except that, offals were mainly purchased at butcher shops. The second objective in this study was to determine the sensory characteristics and consumer acceptance of sausages with 10% fat, 30% edible meat waste and 50% edible meat waste. Sensory descriptive attributes such as appearance, texture, colour, taste, flavour and overall acceptance of the sausage were evaluated by sensory panel (n = 60). The sensory panel comprised of students from undergraduates, post-graduates, post-doctoral fellows and lecturers at the University of Fort Hare. The findings of the study indicated that 50% replacement of xiii edible meat waste was similar to the commercial 10% fat with regard to several sensory attributes and pooled liking. Therefore, the utilization of the edible meat waste in production of sausages has the potential to increase profitability in meat industry and minimise meat waste in the industry. However, the cooking method that was more acceptable to consumers in this study was using the microwave as compared to oven-grilling. Furthermore, the effects of different cooking methods (microwave and oven-grilling) on proximate and mineral composition of the formulated sausages were determined. However, the cooking process appeared to have a significant effect on most of the minerals in the sausage. The cooking methods had a significant effect at P <0.01 on the nutrients composition of the formulated sausage. It was observed that the nutritional values of the sausage was better preserved after the cooking process due to higher mean values obtained after cooking. The mean values for calcium (173.1, 221.76, 231.29), potassium (444.57, 158.58, 156.67), magnesium (84.43, 257.97, 127.27), zinc (52.94, 35.27, 27.13), copper (8.8, 7.07, 4.44), manganese (8.74, 0.65, 0.08), sodium (589.42, 604.45, 529.79) and iron (63.3, 85.38, 74.81) in cooked. And the mean values for calcium (286.18, 132.18, 114.79), potassium (206.64, 113.83, 207.81), magnesium (189.89, 33.97, 48.11), zinc (61.05, 28.09, 26.44), copper (2.92, 2.73, 3.89), manganese (1.42, 0.11, 0.35), sodium (566.47, 530.79, 527.35) and iron (77.56, 58.68, 45.42) in uncooked sausage varied greatly among the treatments. Although, the disparities in the mineral content may be attributed to the different edible meat waste from different parts of the cattle which are either from feedlot or pastured based. In regard to the results obtained from proximate and mineral composition, microwave cooking method was found to be the best cooking technique for healthy eating. Finally, the effect of frying with two different oils (sunflower oil and olive oil) on the fatty acid composition of sausage made with edible meat waste was examined. The results revealed that beef sausage containing 70% edible meat wastes and 30% beef (T1) had a higher fat content xiv (25.7%±0.83%) than other treatments. On the other hand, beef sausage fortified with 10% fat and 90% beef (T3) had the lowest fat content but highest FFDM (55.85±0.57%) and moisture content (69.15±0.62) than other treatments. Despite the increase in omega-3: omega-6 fatty acid ratio in the sausage treatments after cooking, the mean value of omega-3: omega-6 fatty acid ratio was greater than 1:5 (0.2) which is within the FAO/WHO recommended range. The omega-3: omega-6 association is well-known for its importance in the diet because it is a key factor for balanced eicosanoid production in the living organism. The significant reduction in saturated fatty acids after cooking showed that there could also be a positive influence on the human health if consumed. Therefore, it may be concluded from the findings of the study that sausage made with edible meat waste as fat replacer is safe for human consumption.
- Full Text:
- Date Issued: 2019
- Authors: Oluwasegun, Babatunde Alao
- Date: 2019
- Subjects: Meat -- Quality
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10353/19021 , vital:40094
- Description: Meat processing at the abattoir provides meat by product and waste while, the major part of the muscle which constitutes a third is edible. The edible by products (EBP) of meat have a notable position in our day-to-day life and are used in diverse forms. However, the quality of offal meat may differ according to intrinsic and extrinsic attributes that may occasionally be shaped by the attitude of consumers towards the products. Therefore, the first objective of this thesis focused on features that might influence consumer preferences and their perception of offal meat. A total of 202 consumers from three Municipalities in Amathole District were randomly sampled using exponential nondiscriminative snowball sampling. Data were gathered through a structured questionnaire containing open ended and closed ended questions. The study showed that consumers were more influenced by the freshness, price and availability of the product and these factors are used to determine the purchase outlet. Differences were observed in the offal meat consumption between the age groups. Age groups 25-34 (29.7%) and 35-44 (27.4%) showed the highest offal meat consumption, while the decline was observed in age groups of 55-64 (11.9%), 65- 74 (5.9%) and 75-85 (0.01%) respectively. The most preferred purchase point for offal meat in this study was in butcheries. However, it was observed that the factors influencing offal consumption in Amathole District were similar to meat consumption except that, offals were mainly purchased at butcher shops. The second objective in this study was to determine the sensory characteristics and consumer acceptance of sausages with 10% fat, 30% edible meat waste and 50% edible meat waste. Sensory descriptive attributes such as appearance, texture, colour, taste, flavour and overall acceptance of the sausage were evaluated by sensory panel (n = 60). The sensory panel comprised of students from undergraduates, post-graduates, post-doctoral fellows and lecturers at the University of Fort Hare. The findings of the study indicated that 50% replacement of xiii edible meat waste was similar to the commercial 10% fat with regard to several sensory attributes and pooled liking. Therefore, the utilization of the edible meat waste in production of sausages has the potential to increase profitability in meat industry and minimise meat waste in the industry. However, the cooking method that was more acceptable to consumers in this study was using the microwave as compared to oven-grilling. Furthermore, the effects of different cooking methods (microwave and oven-grilling) on proximate and mineral composition of the formulated sausages were determined. However, the cooking process appeared to have a significant effect on most of the minerals in the sausage. The cooking methods had a significant effect at P <0.01 on the nutrients composition of the formulated sausage. It was observed that the nutritional values of the sausage was better preserved after the cooking process due to higher mean values obtained after cooking. The mean values for calcium (173.1, 221.76, 231.29), potassium (444.57, 158.58, 156.67), magnesium (84.43, 257.97, 127.27), zinc (52.94, 35.27, 27.13), copper (8.8, 7.07, 4.44), manganese (8.74, 0.65, 0.08), sodium (589.42, 604.45, 529.79) and iron (63.3, 85.38, 74.81) in cooked. And the mean values for calcium (286.18, 132.18, 114.79), potassium (206.64, 113.83, 207.81), magnesium (189.89, 33.97, 48.11), zinc (61.05, 28.09, 26.44), copper (2.92, 2.73, 3.89), manganese (1.42, 0.11, 0.35), sodium (566.47, 530.79, 527.35) and iron (77.56, 58.68, 45.42) in uncooked sausage varied greatly among the treatments. Although, the disparities in the mineral content may be attributed to the different edible meat waste from different parts of the cattle which are either from feedlot or pastured based. In regard to the results obtained from proximate and mineral composition, microwave cooking method was found to be the best cooking technique for healthy eating. Finally, the effect of frying with two different oils (sunflower oil and olive oil) on the fatty acid composition of sausage made with edible meat waste was examined. The results revealed that beef sausage containing 70% edible meat wastes and 30% beef (T1) had a higher fat content xiv (25.7%±0.83%) than other treatments. On the other hand, beef sausage fortified with 10% fat and 90% beef (T3) had the lowest fat content but highest FFDM (55.85±0.57%) and moisture content (69.15±0.62) than other treatments. Despite the increase in omega-3: omega-6 fatty acid ratio in the sausage treatments after cooking, the mean value of omega-3: omega-6 fatty acid ratio was greater than 1:5 (0.2) which is within the FAO/WHO recommended range. The omega-3: omega-6 association is well-known for its importance in the diet because it is a key factor for balanced eicosanoid production in the living organism. The significant reduction in saturated fatty acids after cooking showed that there could also be a positive influence on the human health if consumed. Therefore, it may be concluded from the findings of the study that sausage made with edible meat waste as fat replacer is safe for human consumption.
- Full Text:
- Date Issued: 2019
Electrical, photo-thermal and mechanical degradation analysis of degraded single junction amorphous silicon solar modules
- Osayemwenre, Gilbert Omorodion
- Authors: Osayemwenre, Gilbert Omorodion
- Date: 2019
- Subjects: Solar cells Amorphous semiconductors Silicon
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10353/15211 , vital:40204
- Description: In this present era of sustainable energy development, photovoltaic modules which are based on amorphous silicon cells have immeasurable prospects of contributing meaningfully to the energy demand of the world at large. The global consciousness of environmental safety issues has birthed the rapid demand for the photovoltaic system. However, the production increase is mainly in bulk-type crystalline (c-Si) solar cells. Thus, to meet the high demand of the market, single junction amorphous silicon (a-Si:H) solar cells production must be encouraged through active research in that regard. This could also help to improve its efficiency and reliability. There has recently been a sharp decrease in the production cost of the bulk Si solar cell, but the a-Si:H solar cell still remains the most economically viable in comparison to the other PV technologies. Companies such as Sharp are currently developing large-scale a-Si:H solar modules that can produce an efficiency of 10.5% after the long-term degradation process. To date, a-Si:H is believed to be one of the most promising thin-film PV technologies (Saito et al., 1993; Hamakawa et al., 1994). The cost of a solar PV manufacturing fell by 6% in 2014 (Santa, 2014), this is in accordance with the 2008 cost production forecast; thus, the cost record stands at 0.20 per watt, as reported by the NPD Solar publisher. Amorphous silicon (a-Si) solar modules generate more kilowatt-hour (kWh) of electricity per kilowatt (kW) than crystalline silicon or other technologies of the same capacity of installation. Furthermore, a-Si:H modules have more functional hours per day. Single junction amorphous silicon (a-Si:H) modules can function beyond the peak sun hours, and they also have a better performance on a cloudy day. vii In other words, a 1kW PV system of a-Si:H is expected to generate more electricity per year in comparison to 1kW PV from other technologies, hence there is a low energy payback time. In this study, commercially available single junction amorphous silicon modules were bought from a local market and they were immediately deployed outdoors. The initial reading of the modules, which served as baseline reading, showed an average of 25% decrease in the modules performance, therefore, there is a need for a long term monitoring process to obtain the best and worst performing modules. Measuring the performance parameters of these PV modules under real sun light (IV) provides a better degradation assessment. This conventional assessment cannot provide an in-depth insight responsible for the variation and degradation of the performance parameters. More obscured parameters like recombination current and ideality factor were obtained from the dark IV measurements. However, this is still superficial in a way. The intrinsic parameters were obtained from scanning probe microscopy (SPM) and CV measurements. The study focuses on the degradation analysis of a-Si:H due to an increase in defect density. A rise in the defect concentration is a huge problem because it causes long-term solar cell degradation, which increases the recombination current and decreases the conversion efficiency. Furthermore, it decreases the photo-generating current and reduces the effective efficiency of the solar device. In other words, the electrical output decreases. This research investigates the reduction in a-Si:H modules’ maximum power, and correlates these with a hot spot formation. A PVPM IV tracer was used for the outdoor characterisation of the module’s temperature profile, while the IR camera was used to analyse the hot spot centre. A four probe IV/CV from NMU was used for the indoor assessment of smaller samples cleaved from both the affected and non-affected regions to characterise the electrical variations across the module viii samples. To be precise, in this study, a naturally degraded single junction amorphous silicon module was delaminated and its mechanical properties were analysed and correlated with the contact potential from a Kelvin probe force microscopy (KPFM).
- Full Text:
- Date Issued: 2019
- Authors: Osayemwenre, Gilbert Omorodion
- Date: 2019
- Subjects: Solar cells Amorphous semiconductors Silicon
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10353/15211 , vital:40204
- Description: In this present era of sustainable energy development, photovoltaic modules which are based on amorphous silicon cells have immeasurable prospects of contributing meaningfully to the energy demand of the world at large. The global consciousness of environmental safety issues has birthed the rapid demand for the photovoltaic system. However, the production increase is mainly in bulk-type crystalline (c-Si) solar cells. Thus, to meet the high demand of the market, single junction amorphous silicon (a-Si:H) solar cells production must be encouraged through active research in that regard. This could also help to improve its efficiency and reliability. There has recently been a sharp decrease in the production cost of the bulk Si solar cell, but the a-Si:H solar cell still remains the most economically viable in comparison to the other PV technologies. Companies such as Sharp are currently developing large-scale a-Si:H solar modules that can produce an efficiency of 10.5% after the long-term degradation process. To date, a-Si:H is believed to be one of the most promising thin-film PV technologies (Saito et al., 1993; Hamakawa et al., 1994). The cost of a solar PV manufacturing fell by 6% in 2014 (Santa, 2014), this is in accordance with the 2008 cost production forecast; thus, the cost record stands at 0.20 per watt, as reported by the NPD Solar publisher. Amorphous silicon (a-Si) solar modules generate more kilowatt-hour (kWh) of electricity per kilowatt (kW) than crystalline silicon or other technologies of the same capacity of installation. Furthermore, a-Si:H modules have more functional hours per day. Single junction amorphous silicon (a-Si:H) modules can function beyond the peak sun hours, and they also have a better performance on a cloudy day. vii In other words, a 1kW PV system of a-Si:H is expected to generate more electricity per year in comparison to 1kW PV from other technologies, hence there is a low energy payback time. In this study, commercially available single junction amorphous silicon modules were bought from a local market and they were immediately deployed outdoors. The initial reading of the modules, which served as baseline reading, showed an average of 25% decrease in the modules performance, therefore, there is a need for a long term monitoring process to obtain the best and worst performing modules. Measuring the performance parameters of these PV modules under real sun light (IV) provides a better degradation assessment. This conventional assessment cannot provide an in-depth insight responsible for the variation and degradation of the performance parameters. More obscured parameters like recombination current and ideality factor were obtained from the dark IV measurements. However, this is still superficial in a way. The intrinsic parameters were obtained from scanning probe microscopy (SPM) and CV measurements. The study focuses on the degradation analysis of a-Si:H due to an increase in defect density. A rise in the defect concentration is a huge problem because it causes long-term solar cell degradation, which increases the recombination current and decreases the conversion efficiency. Furthermore, it decreases the photo-generating current and reduces the effective efficiency of the solar device. In other words, the electrical output decreases. This research investigates the reduction in a-Si:H modules’ maximum power, and correlates these with a hot spot formation. A PVPM IV tracer was used for the outdoor characterisation of the module’s temperature profile, while the IR camera was used to analyse the hot spot centre. A four probe IV/CV from NMU was used for the indoor assessment of smaller samples cleaved from both the affected and non-affected regions to characterise the electrical variations across the module viii samples. To be precise, in this study, a naturally degraded single junction amorphous silicon module was delaminated and its mechanical properties were analysed and correlated with the contact potential from a Kelvin probe force microscopy (KPFM).
- Full Text:
- Date Issued: 2019
Efficacy, acceptability and feasibility of mhealth technology in promoting adherence to anti-diabetic therapy and glycaemic control among diabetic patients in Eastern Cape, South Africa”
- Authors: Owolabi, Eyitayo Omolara
- Date: 2019
- Subjects: Diabetes
- Language: English
- Type: Thesis , Doctoral , PhD (Nursing)
- Identifier: http://hdl.handle.net/10353/16792 , vital:40774
- Description: Background: Diabetes mellitus is a disease of a significant public health concern and a leading cause of death and disability worldwide. In Africa, South Africa ranks second among countries with the highest burden of diabetes, and with a poor level of glycaemic control. mHealth technology is an innovative and cost-effective measure of promoting health and the use of text messaging for fostering health is evolving. In South Africa, there is hardly any study involving the use of mobile health technology, including text messaging for promoting health among diabetic patients. Purpose: The aim of this study was to determine the efficacy, feasibility and acceptability of mHealth in promoting adherence and glycaemic control among diabetic patients in resource-poor settings of the Eastern Cape Province of South Africa. Also, the study assessed the impact of text messaging on knowledge, selfmanagement behaviour, self-efficacy and health-related quality of life. Methodology: The study adopted a multi-centre, two-arm, parallel, randomised controlled trial design. Participants were randomly assigned to the intervention (n=108) and control arm (n=108). Participants’ socio-demographic information was obtained using the widely validated WHO STEPwise questionnaire, and a selfdeveloped questionnaire, including previously validated measurement scales were used to obtain information on adherence, self-management behaviour, self-efficacy and health-related quality of life. Participants in the intervention arm received daily text messages related to diabetes management and care for six months. Data were collected at baseline and six months post-intervention. Blood glucose, blood pressure and anthropometric measurements followed standard procedure. Mixed-model analysis was used to assess the impact of the SMS on random blood glucose while xi | P a g e linear and bivariate logistic regression were used to assess for effect on other clinical outcomes. Results: The mean age of the participants was 60.64 (SD± 11.58) years. The majority of the study participants had secondary level of education (95.3%) and earned 1500 to 14200 Rand per month (67.7%). For both the intervention and the control group, majority never used tobacco (98.10% vs 94.40%) or alcohol (88.00% vs 87.00%). Both arms of the study showed improvement in the primary outcome (blood glucose level), with no significant difference, the mean adjusted difference in blood glucose from baseline to six months post-intervention was 0.26 (-0.81 to 1.32), p=0.634. Also, the intervention did not have a significant effect on the secondary outcomes (knowledge, medication adherence, dietary adherence, adherence to physical activity, healthrelated quality of life, self-management behaviour and diabetes distress). Similarly, the intervention did not have any significant effect on secondary clinical outcomes such as weight (p=0.654), body mass index (p=0.439), systolic (p=0.610) and diastolic blood pressure (p=0.535). An overwhelming majority of the participants (90.74%) were pleased with the intervention and felt it was helpful. Of those who took part in the intervention, 91% completed the follow-up study after six months. Conclusion: The use of SMS is a highly acceptable and feasible adjunct to standard clinical care in the promotion of health among diabetic patients in this study setting. Although there was a little improvement, the efficacy of a unidirectional text messaging in promoting health outcomes in this study setting is still doubt
- Full Text:
- Date Issued: 2019
- Authors: Owolabi, Eyitayo Omolara
- Date: 2019
- Subjects: Diabetes
- Language: English
- Type: Thesis , Doctoral , PhD (Nursing)
- Identifier: http://hdl.handle.net/10353/16792 , vital:40774
- Description: Background: Diabetes mellitus is a disease of a significant public health concern and a leading cause of death and disability worldwide. In Africa, South Africa ranks second among countries with the highest burden of diabetes, and with a poor level of glycaemic control. mHealth technology is an innovative and cost-effective measure of promoting health and the use of text messaging for fostering health is evolving. In South Africa, there is hardly any study involving the use of mobile health technology, including text messaging for promoting health among diabetic patients. Purpose: The aim of this study was to determine the efficacy, feasibility and acceptability of mHealth in promoting adherence and glycaemic control among diabetic patients in resource-poor settings of the Eastern Cape Province of South Africa. Also, the study assessed the impact of text messaging on knowledge, selfmanagement behaviour, self-efficacy and health-related quality of life. Methodology: The study adopted a multi-centre, two-arm, parallel, randomised controlled trial design. Participants were randomly assigned to the intervention (n=108) and control arm (n=108). Participants’ socio-demographic information was obtained using the widely validated WHO STEPwise questionnaire, and a selfdeveloped questionnaire, including previously validated measurement scales were used to obtain information on adherence, self-management behaviour, self-efficacy and health-related quality of life. Participants in the intervention arm received daily text messages related to diabetes management and care for six months. Data were collected at baseline and six months post-intervention. Blood glucose, blood pressure and anthropometric measurements followed standard procedure. Mixed-model analysis was used to assess the impact of the SMS on random blood glucose while xi | P a g e linear and bivariate logistic regression were used to assess for effect on other clinical outcomes. Results: The mean age of the participants was 60.64 (SD± 11.58) years. The majority of the study participants had secondary level of education (95.3%) and earned 1500 to 14200 Rand per month (67.7%). For both the intervention and the control group, majority never used tobacco (98.10% vs 94.40%) or alcohol (88.00% vs 87.00%). Both arms of the study showed improvement in the primary outcome (blood glucose level), with no significant difference, the mean adjusted difference in blood glucose from baseline to six months post-intervention was 0.26 (-0.81 to 1.32), p=0.634. Also, the intervention did not have a significant effect on the secondary outcomes (knowledge, medication adherence, dietary adherence, adherence to physical activity, healthrelated quality of life, self-management behaviour and diabetes distress). Similarly, the intervention did not have any significant effect on secondary clinical outcomes such as weight (p=0.654), body mass index (p=0.439), systolic (p=0.610) and diastolic blood pressure (p=0.535). An overwhelming majority of the participants (90.74%) were pleased with the intervention and felt it was helpful. Of those who took part in the intervention, 91% completed the follow-up study after six months. Conclusion: The use of SMS is a highly acceptable and feasible adjunct to standard clinical care in the promotion of health among diabetic patients in this study setting. Although there was a little improvement, the efficacy of a unidirectional text messaging in promoting health outcomes in this study setting is still doubt
- Full Text:
- Date Issued: 2019