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Changing gender roles: challenges and strategies of female headship in Motherwell

  • Authors: Kadaluka, Gloria Thamo
  • Date: 2019
  • Subjects: Gender roles
  • Language: English
  • Type: Thesis , Masters , MA
  • Identifier: http://hdl.handle.net/10948/44541 , vital:38138
  • Description: For decades, research has examined men’s perceptions of the changing gender roles, highlighting the masculinity crisis and challenges men encounter due to the decreasing male provider role. Yet, studies have not explored women’s perceptions about these changing roles, which have consequentially enabled them to become female-headed households (FHHs). Part of the problem is that in theory, FHHs have indeed been classified as the poorest of the poor. Nevertheless in practice, governments have neglected efforts to support this group. In South Africa, research on challenges of FHHs is quantitative and portrays an overgeneralised image of poverty in FHHs. This study set out to develop a better understanding of how women make sense of the changing roles, in an attempt to investigate the processes through which women assume their headship status and to examine their challenges and strategies as FHHs. Using a qualitative research design in the form of a case study with a phenomenological study orientation, the study identified 40 female participants and the data was collected using in-depth interviews. Data was analysed through inductive thematic analysis. Findings indicated that female headship occurs through an identifiable process and most women were never married, divorced, separated or widowed. Thus, single motherhood is by choice, because it is a choice for independence. The significant obstacle hindering social progress is that women support the changing gender roles, while at the same time utilising linguistic repertoires to hold on to traditional gender role beliefs that reinforce patriarchy. Their also challenges manifested in a similar behavioral fashion, suggesting the intergenerational transmission of poverty. Poor education, sex for jobs, feminisation of labour, teenage pregnancies, burden of care, dependency burden, discrimination, absence of fathers and inability to balance work and family, are challenges that put FHHs under a sustained attack. These findings indicate that despite being poor, women do not view themselves as victims of poverty. They exercise urgency through forging social capital, salaries and child support grants. However, women are stuck in a poverty trap because their relations of exchange are limited to those women who are equally poor.
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  • Date Issued: 2019

Characterisation of single event effects and total ionising dose effects of an intel atom microprocessor

  • Authors: Malinda, Muema
  • Date: 2019
  • Subjects: Microprocessors , Mechatronics
  • Language: English
  • Type: Thesis , Masters , MEng
  • Identifier: http://hdl.handle.net/10948/41875 , vital:36605
  • Description: The rapid advancements of COTS microprocessors compared to radiation hardened microprocessors has attracted the interest of system designers within the aerospace sector. COTS microprocessors offer higher performance with lower energy requirements, both of which are desired characteristics for microprocessors used in spacecraft. COTS microprocessors, however, are much more susceptible to radiation damage therefore their SEE and TID responses needs to be evaluated before they can be incorporated into spacecraft. This thesis presents the process followed to evaluate said characteristics of a COTS Intel Atom E3815 microprocessor mounted on a DE3815TYBE single board PC. Evaluation of the SEE response was carried out at NRF iThemba Labs in Cape Town, South Africa where the device was irradiated by a proton beam at 55.58 MeV and with varying beam currents. The device showed a higher sensitivity to functional interrupts when running with the onboard cache on compared to when running with the cache off, as would be expected. The cross-sections, respectively, are: 4.5𝑥 10−10 𝑐𝑚2 and 2.8 𝑥 10−10 𝑐𝑚2. TID testing on the other hand was carried out at the irradiation chamber of FruitFly Africa in Stellenbosch, South Africa. The test device was irradiated by gamma radiation from a Cobalt-60 source at a dose rate of 9.7kRad/h and to a total dose of 67.25kRad. Noticeable TID degradation, in the form of leakage currents, was observed once a total dose of about 20kRad was absorbed. The device then completely failed once a total dose of approximately 32kRad was absorbed. These results suggest that the E3815 microprocessor would not be suitable for long term missions that require higher TID survivability. The processor could however be considered for short term missions launched into polar or high incline orbits where the dose rate is relatively low, and the mission is capable of tolerating functional interrupts.
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  • Date Issued: 2019

Characterization and antibiogram fingerprints of Enterobacteriaceae and Listeria monocytogenes in irrigation water and agricultural soil samples collected from Amathole and Chris Hani District Municipalities in the Eastern Cape Province, South Africa

  • Authors: Iwu, Chidozie Declan
  • Date: 2019
  • Subjects: Listeria monocytogenes Enterobacteriaceae
  • Language: English
  • Type: Thesis , Masters , MSc
  • Identifier: http://hdl.handle.net/10353/17187 , vital:40864
  • Description: Characterization and antibiogram fingerprints of Enterobacteriaceae and Listeria monocytogenes in irrigation water and agricultural soil samples collected from Amathole and Chris Hani District Municipalities in the Eastern Cape Province, South Africa
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  • 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.
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  • Date Issued: 2019

Charting freedom: inequality beliefs, preferences for redistribution, and distributive social policy in contemporary South Africa

  • Authors: Roberts, Benjamin J
  • Date: 2019
  • Subjects: South Africa -- Economic conditions South Africa -- Economic policy South Africa -- Social policy , Democracy -- Economic conditions -- South Africa Race discrimination -- South Africa Poverty -- South Africa Equality -- South Africa
  • Language: English
  • Type: text , Thesis , Doctoral , PhD
  • Identifier: http://hdl.handle.net/10962/64999 , vital:28644
  • Description: While the transition to democracy in South Africa extended civil and political rights and freedoms to all South Africans, there has been disagreement over the preferred nature and scope of social rights within post-apartheid society, reflecting debates over the trajectory of economic policy. Appreciable developmental gains have been made by the state over the last quarter-century, yet the challenges of poverty, unemployment and inequality persist, coupled with mounting popular discontent with the pace of transformation and political accountability. This has led to fundamental questions about social justice, restitution, and the kind of society we wish to promote. Appeals for a more inclusive, transformative social policy have also emerged, arguing that a wider vision of society is required involving multiple government responsibilities and informed by an ethic of equality and social solidarity. Against this background, in this thesis I study the views of the South African public towards economic inequality, general preferences for government-led redistribution, as well as support for social policies intended to promote racial and economic transformation. The research has been guided by several overarching questions: To what extent do South Africans share common general beliefs about material inequality? Does the public exhibit a preference for government redistribution in principle? And how unified or polarised are South Africans in their support for specific redress policies in the country? Responding to these questions has been achieved by drawing on unique, nationally representative data from the South African Social Attitudes Survey (SASAS), which has enabled me to chart social attitudes over a period of almost fifteen years between late 2003 and early 2017. Use has also been made of social citizenship as a guiding conceptual framework to understanding social policy predispositions and analysing attitudinal change. The results demonstrate that the public is united in its awareness of and deep concern about economic inequality. Since the early 2000s, a significant majority has consistently expressed the view that the income gap in the country is too large, articulated a strong preference for a more equitable social structure, and acknowledged the class and social tensions that economic inequality has produced. There is also a preference for a narrowing of earnings disparities, a more generous minimum wage, and regulatory limits on executive pay. While this suggests a desire for fair and legitimate remuneration, the analysis also reveals that South Africans are willing to tolerate fairly high levels of inequality. Nonetheless, these beliefs are generally interpreted as a desire for a more equitable and fair society. This preference for change is reflected in a fairly strong belief that government should assume responsibility for reducing material disparities. One’s social position, mobility history, awareness of inequality, political leaning and racial attitudes all have a bearing on how weak and strong this predisposition is, but the normative demand for political redistribution remains fairly widely shared irrespective of these individual traits. Greater polarisation is however evident with respect to redistributive social policy, especially measures designed to overcome historical racial injustice (affirmative action, sports quotas, and land reform). These intergroup differences converge considerably when referring to class-based policy measures. One surprising finding is the evidence that South Africa’s youngest generation, the so-called ‘Born Frees’, tend to adopt a similar predisposition to redress policy as older generations, thus confounding expectations of a post-apartheid value change. I conclude by arguing that there seems to be a firmer basis for a social compact about preferences for interventions designed to produce a more just society than is typically assumed. Intractably high levels of economic inequality during the country’s first quarter-century of democracy is resulting in a growing recognition of the need for a stronger policy emphasis on economic inequality in South Africa over coming decades if the vision enshrined in the Freedom Charter and the Constitution is to be realised. South Africans may not be able to fully agree about the specific elements that constitute a socially just response to economic inequality. Yet, the common identification of and concern with redressable injustice, coupled with a broad-based commitment to government redistribution and classbased social policies, could serve as a foundation on which to rekindle the solidaristic spirit of 1994 and forge progress towards a more equitable society.
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  • Date Issued: 2019

Cheetah Acinonyx jubatus behaviour and resource use in response to other African large carnivores

  • Authors: Cornhill, Kristina
  • Date: 2019
  • Subjects: Cheetahs -- Africa
  • Language: English
  • Type: Thesis , Doctoral , PhD
  • Identifier: http://hdl.handle.net/10948/44735 , vital:38169
  • Description: Competition occurs between species for shared resources. Subordinate species employ resource selection to shift their resource use away from that of dominant species in order to avoid the negative consequences of competition. Only in Africa is the post-Pleistocene large carnivore guild intact, consisting of lions Panthera leo, spotted hyaenas Crocuta crocuta, leopards Panthera pardus, cheetahs Acinonyx jubatus, and African wild dogs Lycaon pictus. Therefore, only in Africa can we explore how large carnivores co-exist with one another in a diverse community. Cheetahs are a subordinate member of the large carnivore guild due to their small stature and solitary nature. However, we still do not fully understand how competition shapes cheetah behaviour and resource use. I used cheetahs as a model subordinate predator to determine the behavioural responses and resource selection of cheetah in response to assumed competition from other large carnivores. I experimentally explored the behavioural response of cheetah to large carnivore scent sources (scats) and their presence at cheetah scent-marking sites to test for avoidance of such cues. Moreover, using unplanned experiments based on the resource use of cheetahs in the absence and then presence of lions (assessing space and time use by cheetah) and African wild dogs (assessing prey use by both species), I evaluated resource selection by cheetahs as a way to reduce competition with these large carnivores. In addition, I measured spatial and temporal partitioning between cheetahs and all four large carnivores at camera trap sites. Finally, I assessed whether cheetahs responded to competitors using a long term proactive response or a short term reactive response. I found that all four of the other large carnivores in the guild shaped cheetahs resource use, however, all did so on different axes in accordance with the niche complementarity hypothesis. Lions and spotted hyenas were avoided through time, African wild dogs through space and prey use, and lions and leopards on the spatiotemporal axis. Moreover, I show that cheetahs utilize a reactive response to competition that allows them to avoid risk while still obtaining necessary resources.
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  • Date Issued: 2019

Chitin hydrolysis with chitinolytic enzymes for the production of chitooligomers with antimicrobial properties

  • Authors: Oree, Glynis
  • Date: 2019
  • Subjects: Chitin -- Biotechnology , Enzymes -- Biotechnology , Hydrolysis , Chitooligomers -- Biotechnology
  • Language: English
  • Type: text , Thesis , Masters , MSc
  • Identifier: http://hdl.handle.net/10962/67887 , vital:29165
  • Description: There are many diseases and illnesses in the world that require new drug treatments and chitin has been shown to produce chitooligomeric derivatives which exhibit promising antimicrobial and immune-enhancing properties. However, the rate-limiting step is associated with the high recalcitrance of chitinous substrates, and low hydrolytic activities of chitinolytic enzymes, resulting in low product release. To improve and create a more sustainable and economical process, enhancing chitin hydrolysis through various treatment procedures is essential for obtaining high enzyme hydrolysis rates, resulting in a higher yield of chitooligomers (CHOS). In literature, pre-treatment of insoluble biomass is generally associated with an increase in accessibility of the carbohydrate to hydrolytic enzymes, thus generating more products. The first part of this study investigated the effect of alkali- (NaOH) and acid pre-treatments (HCl and phosphoric acid) on chitin biomass, and chemical and morphological modifications were assessed by the employment of scanning electron microscopy (SEM), Fourier Transform Infrared Spectroscopy (FTIR), Energy-Dispersive X-ray spectrometery (EDX) and x-ray diffraction (XRD). Data obtained confirmed that pre-treated substrates were more chemically and morphologically modified. These results confirmed the fact that pre-treatment of chitin disrupts the structure of the biomass, rendering the polymer more accessible for enzymatic hydrolysis. The commercial chitinases from Bacillus cereus and Streptomyces griseus (CHB and CHS) are costly. Bio-prospecting for other chitin-degrading enzymes from alternate sources such as Oidiodendron maius, or the recombinant expression of CHOS, was a more economically feasible avenue. The chit1 gene from Thermomyces lanuginosus, expressed in Pichia pastoris, produced a large range CHOS with a degree of polymerisation (DP) ranging from 1 to above 6. TLC analysis showed that O. maius exhibited chitin-degrading properties by producing CHOS with a DP length of 1 to 3. These two sources were therefore successful in producing chitin-degrading enzymes. The physico-chemical properties of commercial (CHB and CHS) and expressed (Chit1) chitinolytic enzymes were investigated, to determine under which biochemical conditions and on which type of biomass they can function on optimally, for the production of value-added products such as CHOS. Substrate affinity assays were conducted on the un-treated and pre-treated biomass. TLC revealed that chitosan hydrolysis by the commercial chitinases produced the largest range of CHOS with a DP length ranging from 1 to 6. A range of temperatures (35-90oC) were investigated and CHB, CHS and Chit1 displayed optimum activities at 50, 40 and 45 oC, respectively. Thermostability studies that were conducted at 37 and 50oC revealed that CHB and CHS were most stable at 37oC. Chit1 showed great thermostablity at both temperatures, rendering this enzyme suitable for industrial processes at high temperatures. pH optima studies demonstrated that the pH optima for CHB, CHS and Chit1 was at a pH of 5.0, with specific activities of 33.459, 46.2 and 5.776 μmol/h/mg, respectively. The chain cleaving patterns of the commercial enzymes were determined and exo-chitinase activity was exhibited, due to the production of CHOS that were predominantly of a DP length of 2. Enzyme binary synergy studies were conducted with commercial chitinases (CHB and CHS) on colloidal chitin. Studies illustrated that the simultaneous combination of CHB 75%: CHS 25% produced the highest specific activity (3.526 μmol/h/mg), with no synergy. TLC analysis of this enzyme combination over time revealed that predominantly chitobiose was produced. This suggested that the substrate crystallinity and morphology played an important role in the way the enzymes cleaved the carbohydrate. Since CHOS have shown great promise for their antimicrobial properties, the CHOS generated from the chitinous substrates were tested for antimicrobial properties on Bacillus subtilis, Escherichia coli, Klebsiella and Staphlococcus aureus. This study revealed that certain CHOS produced have inhibitory effects on certain bacteria and could potentially be used in the pharamceutical or medical industries. In conclusion, this study revealed that chitinases can be produced and found in alternate sources and be used for the hydrolysis of chitinous biomass in a more sustainabe and economically viable manner. The chitinases investigated (CHB, CHS and Chit1) exhibited different cleaving patterns of the chitinous substrates due to the chemical and morphological properties of the biomass. CHOS produced from chitinous biomass exhibited some inhibitory effects on bacterial growth and show potential for use in the medical industry.
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  • Date Issued: 2019

Civil society engagement with water governance at a local government scale in South Africa

  • Authors: Weaver, Matthew James Thanduxolo
  • Date: 2019
  • Subjects: Government accountability -- South Africa , Civil Society -- South Africa , Political participation -- South Africa , Local government -- South Africa , Water supply -- Management , Water resources development -- South Africa , Water quality management -- South Africa
  • Language: English
  • Type: text , Thesis , Doctoral , PhD
  • Identifier: http://hdl.handle.net/10962/151316 , vital:39051
  • Description: The South African state’s ideological commitment to a participatory approach to managing water resources and delivering services in a way that includes all stakeholders warrants critical analysis.Realising this ideological commitment has proved challenging, due largely to the complex historical, political, social, and environmental context of integrated water resource management (IWRM) in South Africa. The overarching aim of this study was to explore and expand the learning of civil societyparticipating in water governance processes at a local government scale. To address this aim a single, in-depth, four-year case study into civil society participation in water governance in the Makana Local Municipality in the Eastern Cape Province of South Africa was conducted between 2014 and 2018. The case study comprised two research phases. Both phases of the research were conducted using an adaptive transdisciplinary and participatory action research approach underpinned by General Complexity Theory. Located at the research-practice interface, the study sought to be transformative and advance both scientific research and societal goals. Qualitative research methods and inductive and deductive modes of inference were used to collect and analyse the data respectively. In the first phase of the study, a Communities of Practice theoretical framing was adopted to investigate the emergence, practice and learning of a civil society organisation (CSO), Water for Dignity (WfD), in response to household water service delivery issues in the municipality. This phase served to build an understanding of factors that enabled and constrained the practice of WfD in addressing local water service issues, and of their role as social learning agents in building water-related knowledge in their community. As participation with the first civil society organisation fragmented, the opportunity arose for local government, the National Department of Water and Sanitation and civil society to co-engage. This opened up the second phase of the research during which the role of a multi-stakeholder platform, the Makana Water Forum (MWF), in enabling democratic water governance was investigated. The MWF was South Africa’s first catchment management forum with an integrated water service and water resource management agenda. In this phase, the study drew on interventionist methodology, Change Laboratory, from Cultural Historical Activity Theory (CHAT) to 1) describe the historical development, composition and shared purpose of the MWF multi-activity system constellation; and to 2) guide participants through seven learning actions (expansive learning cycle) to identify, analyse, model and implement remedial actions to problematic aspects (contradictions) of the MWF practice. Participants of the Change Laboratory workshops built their individual and collective transformative agency (deliberate actions to transform a problematic situation) as they navigated the expansive learning process. The development of this agency was identified through a micro-analysis of agentive talk. The two phases served to advance the exploration of civil society participation from informal participation to address water issues, to formal participation in water governance processes at a local government scale. Findings from the first phase of the research revealed that dedicated and sustained support of partners with distributed expertise and the highly motivated core members of WfD enabled the practice and emergence of the civil society organisation. However, factors such as poor internal leadership, power dynamics between supporting partners, socio-economic constraints and a deeply embedded lack of agency were found to be key constraining factors to WfD’s practice. Findings revealed that learning at WfD team level occurred in four ways, through learning as belonging, learning as doing, learning as experiencing and learning as becoming. The WfD CSO was able to catalyse social learning related to personal water rights; and best practices for improving water quality and water conservation in their wider community of practice. Social learning was fostered mainly through structured citizen engagements offered by WfD. The research provides evidence that civil society organisations can play an important role in bridging water-related knowledge gaps and can foster active citizenship in South African communities. However, despite significant inputs of support and resources through the engaged transdisciplinary research process, the practice and learning outcomes of WfD had a marginal transformative impact on improving the citizen’s every-day water service experiences. Findings from the second phase of the study revealed the MWF to resemble a multi-activity system constellation with a multiple, partially overlapping. interests related to the management of water. The establishment, function and contradictions constraining the function of the MWF were influenced by past cycles of participatory water governance-related activity and practice at national and local scales. Through the Change Laboratory process, 25 contradictions were identified that appeared to constrain the ability of the MWF to enable inclusive and meaningful participatory water governance. Through a process of expansive learning, participants sought to overcome three sets of contradictions grouped as Problem Themes: lack of clear focus of the MWF; representation, representivity and nonattendance; and the MWF relationship with the Makana Local Municipality. Remedial actions modelled and those enacted have improved aspects of the function of the MWF (such as diversified modes of engagement and a more focussed agenda) but have only resulted in incremental shifts towards enabling improved participatory practice, most markedly in building a collaborative relationship and trust between the MWF members, municipal and government officials. The microanalysis of agentive talk revealed seven different expressions of transformative agency. Constraining socio-economic and political conditions and the limited capacity of the coordinating committee of the MWF hindered the development of transformative agency to the extent to which concrete actions were implemented. Findings further revealed that contextualising a Change Laboratory process within the adaptive cycle of a complex social-ecological system, and the particular opportunity context the system presents, could inform the enactment of agency and its potential impact on the transformation of the system. The intervention with the MWF was too short a process to clearly observe the effects of transformative actions on the sustainability of the Makana Local Municipality water system. However, long-chain transformative agency through the development of one-on-one engagements, learning journeys and a reflexive component to the MWF engagements could support transformative pathways to sustainability in the municipality and water management system. The study contributes in-depth insight into the key role of learning as a catalyst in transformative processes. Learning improves the collaborative and adaptive capacity of people, and therefore, water management institutions, to manage explicitly for the complexity inherent in “complex” socialecological systems. It provides empirical evidence as to what enables and constrains “real” participation and learning in grass-roots water governance processes in the context of a shifting national drive towards a more adaptive and developmental Integrated Water Resource Management approach. It further provides methodological contributions to 1) the application of the Change Laboratory method with multi-activity system constellations in developing world contexts and 2) value and limitations of extended and engaged transdisciplinary research. Lastly, it provides practical recommendations to the establishment and sustainable function of both community-based CSOs and multi-stakeholder platforms engaging in water governance processes.
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  • Date Issued: 2019

Climatic suitability of Dichrorampha odorata Brown and Zachariades (Lepidoptera: Tortricidae), a shoot-boring moth for the biological control of Chromolaena odorata (L.) R.M. King and H. Robinson (Asteraceae) in South Africa

  • Authors: Nqayi, Slindile Brightness
  • Date: 2019
  • Subjects: CLIMEX , Chromolaena odorata -- Biological control -- South Africa , Tortricidae -- South Africa , Bioclimatology -- Software
  • Language: English
  • Type: text , Thesis , Masters , MSc
  • Identifier: http://hdl.handle.net/10962/92208 , vital:30681
  • Description: Biological control using natural enemies introduced from the native range is an integral component of the management of Chromolaena odorata, a serious invader in the eastern regions of South Africa. A number of biological control agents for C. odorata have been released in South Africa, and one of them, Dichrorampha odorata, has failed to establish. To understand if D. odorata failed to establish due to climate incompatibility, its thermal physiology was investigated. Thermal tolerance data were used to determine the developmental thresholds and number of generations that D. odorata is capable of going through in South Africa per year. These predictions were generated using CLIMEX temperature data and the degree-day parameters K and t0. Developmental time decreased with increasing temperatures ranging from 20 °C to 30°C, with immature stages not able to complete development at 18°C and 32°C. The developmental threshold, to, was determined as 8.45 °C with 872.4 degree-days required to complete development (K), indicating that D. odorata is capable of producing a maximum number of 6.5 generations per year in South Africa. The CLIMEX data indicated that the east coast regions of South Africa, which are the heaviest invaded areas by C. odorata in South Africa, were climatically most suitable for D. odorata to. D. odorata lower (LLT50) and upper (ULT50) lethal temperatures were -4.5°C and 39.64°C for larvae and 1.83 and 41.02°C for adults, and D. odorata adults were able to maintain locomotory functioning at 4.4 to 43.7°C, respectively. Acclimation at low and high temperatures indicate that when D. odorata was kept at a lower temperature of 20°C for 7 days, it became tolerant to warmer and cooler temperatures (1.95 and 44.41°C) when compared to D. odorata reared at 25°C (3.36 and 43.67°C) and 30°C (5.92 and 42.93°C). Dichrorampha odorata is therefore climatically suitable for release and should establish in South Africa to control C. odorata. The establishment and persistence of D. odorata will not be limited by climatic conditions but rather the distribution of its host weed, C. odorata in South Africa. Also, this study presents a decision-making protocol for the release of D. odorata to allow better performance in the field.
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  • Date Issued: 2019

Clinical psychologists’ perceptions of the phenomenon of schizophrenia in a psychiatric setting in the Eastern Cape, South Africa

  • Authors: Hamman, Colette
  • Date: 2019
  • Subjects: Schizophrenia -- Diagnosis -- South Africa , Schizophrenia -- Treatment -- South Africa , Schizophrenics -- Rehabilitation -- South Africa , Schizophrenics -- South Africa -- Case studies
  • Language: English
  • Type: text , Thesis , Masters , MA
  • Identifier: http://hdl.handle.net/10962/71398 , vital:29845
  • Description: Numerous international and South African scholars are critical of the dominant research on the phenomenon of schizophrenia. Rather than refuting dominant biomedical psychiatric conceptualisations of schizophrenia, there is a call for incorporating a focus on the psychology of the person diagnosed with schizophrenia. In South Africa, the integration of the psychosocial components of psychotic experiences into the understanding and treatment of psychosis are still neglected in biomedically-focused psychiatric settings. In relation to this call, the role of clinical psychologists working within these settings seems pertinent. Against this background, this study aimed to explore and describe the perceptions of clinical psychologists, working in a psychiatric setting in South Africa, in relation to the phenomenon of schizophrenia. Informed by a social constructionist theoretical framework, this study utilised a qualitative research design and a semi-structured interview schedule. In-depth, individual interviews were conducted with three clinical psychologists and the transcribed interviews were analysed using thematic analysis. From the data, perceptions were identified as largely polarised in relation to the phenomenon of schizophrenia. These polarised perceptions included: Physical impact of schizophrenia versus social impact of schizophrenia; rehabilitation of schizophrenia versus recovery within schizophrenia; diagnostic frameworks as useful versus diagnostic frameworks as limiting; and institutionally-defined identity versus self-defined identity. In terms of these polarised perceptions, an overarching theme of the medicalisation versus the demedicalisation of schizophrenia was identified. Therefore, the perceptions of clinical psychologists in this study were largely polarised towards either a medicalisation of the phenomenon of schizophrenia or a demedicalisation of it. However, perceptions were also identified that evidenced an integration of the two sides of the polarities, and a holding of tension between seemingly incompatible or incongruent frameworks. The participants perceived psychologists as positioned in the middle ground between the medicalisation and demedicalisation of schizophrenia in a biomedical psychiatric setting. In response to the call for a focus on the psychology of the person diagnosed with schizophrenia, the findings support both the value and the need for an “integration of polarised perceptions”, “holding of the tension”, and “middle ground positioning” of clinicians between medicalised and demedicalised aspects of the phenomenon of schizophrenia.
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  • Date Issued: 2019

Collaborative health literacy development: a World Health Organization workplace health promotion approach to address tobacco use

  • Authors: Duxbury, Theodore Orlando
  • Date: 2019
  • Subjects: Tobacco use -- Health aspects , Smoking -- Health aspects , Employee health promotion , Employee health promotion -- Computer programs , Rhodes University -- Employees -- Tobacco use
  • Language: English
  • Type: text , Thesis , Masters , MPharm
  • Identifier: http://hdl.handle.net/10962/104116 , vital:29930
  • Description: Background: Non-Communicable Diseases (NCDs) are a major global public health threat and tobacco use in particular is the leading cause of preventable illness and mortality globally. Furthermore, vulnerable and socially disadvantaged people get sicker and die sooner, especially because they are at higher risk of being exposed to harmful products such as tobacco and have limited access to health services. Tobacco use also has a major impact on the workplace, adversely affecting work productivity and increasing absenteeism. Both the living and work environments, therefore, play an important role in contributing towards the NCD epidemic. Demographics, culture, behaviour change reluctance and health literacy are all factors which exacerbate tobacco prevalence in South Africa. Workplace health promotion, however, is not well established in many workplaces. This study aimed to develop, implement and evaluate the effectiveness of a culturallysensitive and contextually-appropriate collaborative workplace health promotion literacy programme on tobacco use, utilizing tailored health information leaflets and the Rhodes University peer educators support staff, guided by the World Health Organization Workplace Health Promotion Framework. Method: The research was conducted using a participatory action research approach, which involved four phases: Firstly, the Exploratory phase assessed tobacco-related health promotion policies and practices at Rhodes University; and established facilitating and constraining factors related to tobacco use. Secondly, the Educational health promotion phase involved designing and testing a health promotion educational intervention to address tobacco use related challenges, which took the form of culturally sensitive and appropriate health information leaflets to be used as an educational intervention Thirdly, in the Implementation phase health promotion training workshops were conducted with volunteering Rhodes University Peer Educators. Finally, an Evaluation phase involved evaluating the tobacco health promotion programme presented to the Rhodes University Peer Educators through a focus group discussion; and evaluating Peer Educator recall on the tobacco related health information discussed during the training workshops through a post-post intervention questionnaire. Eight semi-structured interviews (SSIs) and seven focus group discussions (FGDs) were conducted with support staff, peer educators and key stakeholders to establish the need for a comprehensive workplace health promotion initiative, and to identify the facilitating and constraining factors to conducting such an initiative on tobacco use at the University. Three health information leaflets (HILs) were developed collaboratively with the Peer Educators following a series of scientific, end-user testing approaches. The HILs were tested for readability, comprehension, actionability and suitability. A four-day health promotion training programme was conducted to improve user friendliness, memory retention and recall of the HILs by the peer educators and to improve tobacco related health literacy aspects. The participants’ memory recall was evaluated using a pre- and post-, and post-post-intervention questionnaire to evaluate knowledge transfer. The study participants were also equipped with the completed HILs to distribute to their peers and to use as reference sources of information when needed in future. Results: The peer educators and institutional management supported the need for a tobacco workplace health promotion intervention. The intervention and evaluation phase of this study proved that health information material developed was readable, actionable, suitable, userfriendly, culturally sensitive and contextually appropriate. The workshops resulted in a significant increase in the participants’ tobacco related health knowledge. Through the adoption of a collaborative approach to the research, the participants felt empowered and ready to be agents of change amongst their peers in the workplace. Recommendations: The collective use of external expert reviewers, end-user testing techniques and validated computer programmes are recommended to improve the validity of health promotion research outcomes. A longitudinal study that focus on behaviour change, specifically, with health evaluation and monitoring aspects could be conducted as the next step to this study.
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  • Date Issued: 2019

Colloquial terms used in young adults’ talk about sexual practices, sexual subjectivities and sexual desires’

  • Authors: Robertson, Cassandra Ann
  • Date: 2019
  • Subjects: Youth -- Sexual behavior , Sex in popular culture , Communication and sex , Language and sex
  • Language: English
  • Type: text , Thesis , Masters , MSocSc
  • Identifier: http://hdl.handle.net/10962/96551 , vital:31293
  • Description: Much of the growth in sexualities‘ research has taken the form of large scale surveys, but there is also increased interest in qualitative approaches that provide useful insights into the experiential and subjective aspects of sexuality, and illuminate the social and cultural contexts shaping these experiences. The reason for this research is to provide a richer understanding of the language that young people employ when speaking about sexuality. This study examines young adults‘ talk about sexualities with a special focus on the way in which colloquial terms are deployed in this talk and through the presence of gendered and/or heteronormative assumptions. Data consisted of posts off a student-led social media site and the study design employed was a validity check group interview. The social media site allowed its followers to post anonymously about a range of sexualities related issues. Data were analysed thematically, using a deductive, critical, and post-structuralist approach with key insights drawn on from Michael Foucault, Adrienne Rich, Gayle Rubin, Judith Butler and Rosalind Gill. Three overarching themes emerged: young adults spoke to sexual practices, sexual subjectivities and sexual desires. A major focus of this talk is casual sex. This talk showed that there are attempts to undermine gendered and heteronormative power relations, for example, non-normative sexual experiences were not seen as deviant, although those who were engaging in monogamy and casual sex were constructed as deviant sexual subjects. Yet underpinning of these power relations still took place, for example, in the female missing discourse of desire, the internalisation of male sexual desires over female sexual desires and the sexual double standard. There was a clear divide between the sexual practices and sexual subjectivities that were considered to be good and bad. This research therefore has the potential to benefit sexuality interventions by bringing into sharp focus the actual experiences of young adults.
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  • Date Issued: 2019

Communicating in/from the Cave: a communication for development/social change project aimed at enhancing communication, action and learning within the science cave, a learner-led Grade 10 science club in a public school in Makhanda

  • Authors: Bombi, Thandi
  • Date: 2019
  • Subjects: Science -- Study and teaching (Secondary) -- South Africa , Communication in science -- South Africa , Science -- Study and teaching (Secondary) -- South Africa -- Makhanda , Communication in science -- South Africa -- Makhanda , Student centered learning -- South Africa , Student centered learning-- South Africa -- Makhanda
  • Language: English
  • Type: text , Thesis , Masters , MA
  • Identifier: http://hdl.handle.net/10962/96837 , vital:31330
  • Description: This research seeks to design, execute and reflect on a process where the principles and techniques of Communication for Development and Social Change are applied to enhance, support and develop qualitative changes within a learner-led Grade 10 science club at a public school in Makhanda. It draws and reflects on an ethnographic action research (Tacchi et al 2003) cycle proposed to explore the club’s communicative ecology (Foth & Hearn 2007) and resources, and understand how these have the potential to encourage the expression of voice (Couldry 2010: 580) and participation (Carpentier, 2011) in the members of the club. The research then attempts to understand the kind of communication, action and learning that takes place as well as the ways in which the framework is able to support the club (or not). The research uses an ethnographic narrative, told from the perspective of the researcher informed by field notes, interviews and participant reflections written during the intervention. This narrative, alongside an analytical summery of the club’s complex communicative ecology, tells the story of a club building confidence within a closed group and using that to connect with a wider public, articulating its needs, resources and potential supporting stakeholders for the club’s future development. The club is able to share its achievements with a community of peers and uses the platform of Facebook, to communicate with and inspire other like-minded people with an interest in science and their community.
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  • 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
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  • Date Issued: 2019

Community perception of air pollution: health and environmental impact of manganese operations at PE port

  • Authors: Mtati, Vuyani
  • Date: 2019
  • Subjects: Air -- Pollution -- South Africa -- Port Elizabeth , Manganese -- Environmental aspects -- South Africa -- Port Elizabeth Manufacturing industries Environmental health Sustainable development
  • Language: English
  • Type: Thesis , Masters , MBA
  • Identifier: http://hdl.handle.net/10948/41919 , vital:36609
  • Description: The Mining industry in South Africa is viewed as the backbone of the country’s economy; however, while benefiting from this engine of economic development, its impact on the environment and health has been of major concern to different stakeholders. The majority of people acknowledge the role of mining in the economy and the country. Others put more emphasis on public health and the environment. Furthermore, manganese plays an important role in the economic growth and development within the Eastern Cape Province. Responding to recent public concern over manganese dust emissions, Port of Port Elizabeth manager, Rajesh Dana, outlined a five-point manganese management plan formulated by Transnet. Mr. Dana stated the following: “We do not dispute the fact that our manganese operation in the Port of Port Elizabeth creates an inconvenience to port tenants and residents. However, as a responsible corporate citizen we have superior operational and compliance controls in place to mitigate these negative impacts.” Some of the concerns raised by community members are that the manganese ore dust has long term negative effects on the health of this city’s residents, the marine life, as well as the properties within, roughly, a 5km (own opinion estimate) radius of the tanks. Port Elizabeth (Nelson Mandela Bay) has the potential to become a tourism and economic hub within this radius and beyond, and by removing this hazard it will allow for a green environment to be established that gives all the citizens as well as tourists, a place to take part in a healthy lifestyle. Some believe that the city, specifically the CBD area, has the potential to be world renowned for green innovations but having a major hazard in the way, which can be moved to, and better controlled at, Coega IDZ, is not only damaging to the health of its citizens but also the economy of the city. Air pollution affects both physical and human environments. Often, communities that are in close proximity to pollution sources are more vulnerable and experience its greatest effect. As a result, many residents complain of negative health related impacts caused by air pollution which is attributed to industries located close to these communities. About two million deaths annually are attributed to urban air pollution worldwide, which is an indication that air pollution remains an enormous health risk to people. Due to the health impacts on humans, air pollution has also been negatively categorised based on perceptions around the world. The aim of the study was to assess the impact of environmental pollution and public health on the South End, Humewood and Humerail occupants and their perceptions of air quality effects and health risks from the Transnet manganese operation in Port Elizabeth. The present study can be described as a quantitative descriptive survey that uncovered serious levels of pollution in the said areas that had dire health consequences for the people involved. The findings of the study indicate that residents live with the constant dust of a variety of chemical pollutants released both by normal Port operations and by periodic incidents caused by other polluters. They experience chronic respiratory symptoms, burning eyes, hearing deficiency and skin irritations. The study revealed that environmental pollution consequences affecting residents are inversely related to distance from the Port. The results obtained in this study are evidence that environmental pollution, especially manganese in the area, is a definite risk to the health of people living within the surrounding area. Although indicating the need to carry out a comprehensive study, the results call for immediate action to engage community members in order for them to understand the risks associated with the Port operations and prevent continued public over-exposure to environmental pollution.
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  • Date Issued: 2019

Companies creating shared value through their business models

  • Authors: Ncemane, Bonakele
  • Date: 2019
  • Subjects: Business planning , Strategic planning Social responsibility of business Capitalism -- Moral and ethical aspects
  • Language: English
  • Type: Thesis , Masters , MBA
  • Identifier: http://hdl.handle.net/10948/42935 , vital:36712
  • Description: The subject of this treatise was the construct “Creating Shared Value”. The purpose was to explore the business models companies use to create shared value. The study was based on the life insurance industry. The study employed a qualitative paradigm and four Cases were content analysed. It was found that business models used by the insurance industry increase quality of life and thereby increasing social value; further these business models increases economic value for business through the reduction of insurance costs . This mutual and simultaneous creation of economic value and social value is the underlying principle of the Shared Value Construct. Secondly it was found that business models used by the life insurance companies selected for the study manifested hybrid business models with features of both inclusive and social business models components. Practical implications – Policy makers should consider providing universal coverage based on the emerging hybrid business model as an alternative to National Health Insurance business model that is aimed at compulsory membership of citizens to a medical aids. These model enhance early detection of disease’s which promotes better health management and prevention, literature review correlated this with better productivity, less insurance claims and general wellbeing of the citizens.
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  • Date Issued: 2019

Comparative study of phytochemical composition and insecticidal properties of Lemon species from Eastern Cape and KwaZulu-Natal

  • Authors: Nodola, Phumelele
  • Date: 2019
  • Subjects: Phytochemical -- Insecticidal properties Lemon - - Species – Eastern Cape - - South Africa Citrus limon
  • Language: English
  • Type: Thesis , Masters , M Sc
  • Identifier: http://hdl.handle.net/11260/1348 , vital:32261
  • Description: Citrus limon commonly known as lemon is the third most cultivated citrus genus in South Africa mainly cultivated for its juice. This study aims at analysing the chemical composition of Citrus limon waste (leaf and peel) and evaluation of their insecticidal properties. Leaves and peels of Eureka lemons were collected from three South African citrus farms (Addo, Riverside and Mystic), while Lisbon lemons were only collected from two citrus farms (Addo and Riverside) in 2017 and 2018. A total of 36 essential oils were extracted using the Clevenger like apparatus. Analyses of these oils were done using GCMS. An infusion extract of C. limon was prepared according to the standard method and subjected for phytochemical screening to detect and quantify secondary metabolites present. D-Limonene was the major compound identified in all the 36 oils from Eureka and Lisbon peels and leaves (27.9-74.8%). Other dominant compounds identified in Eureka leaf and peel oils were -pinene (5.8-13.2%), -terpinene (4.8-6.7%), geranial (4.0-15.4%), z-citral (6.7-11.7%), sabinene (4.5-6.3%), nerol (4.0-5.4%) and neryl acetate (6.3-9.5%). Some compounds were however present only in some oil such caryophyllene (6.5%) in Mystic dry leaf oil, geraniol (8.0%) in Addo dry leaf oil, as significant compounds. Lisbon leaf and peel essential oils -pinene (4.4- 11.8%), p-cymene (4.2-6.3%), -terpinene (4.4-6.9%), geranial (8.6-17.3%), z-citral (7.1-13.6%), neryl acetate (4.7-9.1%) (5.4-5.9%) were the other prominent peaks identified in the oils. These C. limon essential oils were further tested for insecticidal activities against maize weevils by conducting repellent assay, fumigant assay and contact toxicity; also plant viii powder was used against maize weevils. In general, for all the bioassay, mortality of the insect increased as the contact days with the oil increased. Contact toxicity assays of C. limon peel essential oils were most effective against S. zeamais in which all weevils were dead by day 3 (100% mortality) at 300 μL, while at other concentrations (50, 100, 200 μL) over 50% mortality was observed. The fumigant potential was high with the peel oil with over 50% mortality at 32 and 40 μL in day 4. The oil had moderate repellent effect on the maize weevil. Riverside Eureka dried powder peel was the most effect in all. These results unveil the medicinal potential of South African citrus waste in post-harvest crop protection and good sources of some chemical compounds which are of medicinal value. Furthermore, this study also reveals the economic potential of these wastes in job creation.
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  • Date Issued: 2019

Comparing organic and conventional farming systems in George, South Africa

  • Authors: Swanepoel, Marike
  • Date: 2019
  • Subjects: Organic farming -- South Africa -- George , Sustainable agriculture -- South Africa -- George Agricultural systems -- South Africa -- George
  • Language: English
  • Type: Thesis , Masters , MSc
  • Identifier: http://hdl.handle.net/10948/43946 , vital:37086
  • Description: This study presents some of the findings of a long-term comparative study at the Nelson Mandela University George campus which started in 2014. This research compares the differences in crop yields and soil fertility under conventional and organic farming systems. Although previous research that was conducted will be presented briefly, the main focus of this dissertation is to report on the research results generated during the 2016/17 and 2017/18 cropping seasons. The baseline study (indicator measurements) was done in 2014 and investigated soil fertility before the different farming systems were implemented. The rapid increase in human population threatens food security, especially in developing countries. Climate change together with the degradation of soil and other natural resources due to high-input industrial farming, provide further challenges in terms of agriculture and future food security. Agricultural production in South Africa faces three obstacles: water scarcity, infertile soils and poor institutional support. Therefore, regenerative and sustainable agriculture practices such as organic farming, are increasingly being promoted as an alternative to conventional farming systems in southern Africa. What is the best way of farming? This is the question every farmer is confronted with. Some say organic whilst others say conventional, but how do we determine this? What is the role of crop rotation in pest management, soil fertility and crop yield? So we set up the research to compare the two farming systems so that decisions can be based on sound scientific findings. Results showed a significant increase in the case of the organic yield in season 2016/17 for cabbage and in both seasons (2016/17 & 2017/18) for cowpea and sweet potato, proving that organic farming yields can increase over time. Soil fertility changes from the baseline year (2014) till the end of season 2017/18 were compared. Overall organic farming systems showed very promising results with higher levels of soil pH followed by a significant increase in important soil nutrients (P, K & C) compared to conventional systems. Crop rotation also had positive effects.
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  • Date Issued: 2019

Comparison of consumer perspectives of the natural and commercial synthetic chemical-based mosquito repellent products

  • Authors: Ndoyana, Lusanda
  • Date: 2019
  • Subjects: Insect baits and repellents , Mosquitoes -- Control Consumers -- Attitudes Consumers -- South Africa
  • Language: English
  • Type: Thesis , Masters , MTech
  • Identifier: http://hdl.handle.net/10948/42902 , vital:36704
  • Description: The present study was conducted to determine the perceptions of consumers between the natural mosquito repellent products and the synthetic chemical mosquito repellent products. The perception is that natural mosquito repellent products are more effective than synthetic chemical mosquito repellents based on odour, cost and quality. A comparison of the two products was done in a form of a structured questionnaire where randomly selected participants were given two questionnaires. The participants were asked to provide their perceptions concerning cost, quality and odour. Each participant was also given one formulated natural (green) candle and one synthetic (white) chemical mosquito repellent product. The formulated natural candles contain Oil of Lemon Eucalyptus (OLE) as the active ingredient. OLE is a natural plant-based repellent which is extracted from the leaves and twigs of the lemon-scented gum eucalyptus plant. The results showed that both products were effective in terms of cost, product quality and odour. However, the natural mosquito repellent product was more effective than the synthetic chemical product based on the observed p-value results.
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  • Date Issued: 2019

Comparison of leg dominance and fatigue state on lower extremity kinematics during cutting manoeuvres in male soccer players

  • Authors: Nienaber, Madeleine
  • Date: 2019
  • Subjects: Human mechanics , Kinematics Kinesiology Sports injuries Soccer players -- South Africa
  • Language: English
  • Type: Thesis , Masters , MA
  • Identifier: http://hdl.handle.net/10948/42880 , vital:36702
  • Description: Soccer is one of the most popular sports played in South Africa and around the world. Soccer is a high intensity, semi-contact sport which is associated with an increased prevalence of injuries, especially to the lower extremities. Central and neuromuscular fatigue is believed to cause changes to kinetic and kinematic patterns of soccer players which may increase the risk for injuries, specifically related to the anterior cruciate ligament (ACL). To investigate the effects of fatigue on knee joint kinematics during the stance phase of a cutting manoeuvre of the dominant and non-dominant legs. A quantitative approach, more specifically, an experimental study design was adopte and a quasi-experimental study design was selected. A ‘within-participants post-test only design’ was used, which is also known as a ‘repeated measures design’ because all participants were ‘repeatedly’ measured under each experimental condition. Due to the non-randomization of the quasi-experimental design, non-probability sampling was utilized to sample the population group for the proposed study. A total of 13 male soccer players volunteered for the study. The participants had the following characteristics (mean ± SD): age 22.15 ± 2.77 years; height 169.64 ± 5.75 cm and weight 64.60 ± 7.04 kg. Non-significant differences within hip joint kinematics were observed between the dominant and non-dominant legs in a non-fatigued state in all three planes of motion (F = 0.61, p = 0.55). Similar kinematic characteristics were observed for the knee joint (F = 1.25, p = 0.48) and the ankle joint (F = 3.33, p = 0.64). Non-significant differences were also observed during the fatigued state in all three planes of motion for the hip joints (F = 8.98, p = 0.72), knee joints (F = 5.21, p = 0.41) and ankle joints (F = 0.21, p = 0.12). Peak vertical forces were however significantly different between the fatigued state compared to the non-fatigued state during the cutting manoeuvre (F = 23.51, p = 0.035), thereby indicating that neuromuscular fatigue may influence landing forces on impact during a directional change. The effect of leg dominance did not have a statistically significant impact on any kinematic measures as well as the interactions between fatigue and non-fatigue trials were also not observed for any of the kinematic parameters. Several initial contact and peak stance–phase lower limb-joint rotations were influenced by fatigue during the execution of the sub-maximal 60° cutting manoeuvre. The main effect of fatigue produced an increase in knee internal rotation and hip abduction and a decrease in peak knee abduction angles compared to non-fatigue, but they were not statistically significant. Significant differences were found between dominant and non-dominant legs as well as between fatigue and non-fatigue with ankle pronation (p=0.007) and ankle external rotation (p=0.033). Knee abduction angle during cutting (p=0.061) also showed an effect even though not statistically significant. The purpose was to examine the combined effects of leg dominance and fatigue on lower-limb biomechanics during a sub-maximal 60° cutting manoeuvre. The conclusion of the present study related to limb dominance was that no statistically significant differences were evident for any of the dependent variables (limb dominance; fatigue state) related to the independent variables (i.e. joint [hip, knee, ankle], contact time, ground reaction however, between-subject fatigue variations that is large enough could negatively impact the biomechanical data comparisons. Future research should target specific locations of fatigue within a general fatigue paradigm and develop standardized tasks to achieve this.
  • Full Text:
  • Date Issued: 2019
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