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In vitro anti-cancer efficacy and phyto-chemical screening of solvent extracts of Kigelia africana (Lam.) Benth

  • Authors: Mukavi, Justus W , Mayeku, Philip W , Nyaga, Justine M , Kituyi, Sarah N
  • Date: 2020
  • Subjects: To be catalogued
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/429439 , vital:72610 , xlink:href="https://www.cell.com/heliyon/pdf/S2405-8440(20)31325-6.pdf"
  • Description: Kigelia africana is a medicinal plant growing naturally in many parts of Africa. In Kenya, a water concoction of the plant is used to treat breast and prostate cancers. Laboratory data on its anti-cancer activity and active principles is limited, hence no scientific rationale for its medicinal use. This study reports on in-vitro toxic activities of dichloromethane and methanol extracts of the plant against human breast cancer cells and phytochemical screening of the two extracts.
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  • Date Issued: 2020

In Vitro Release Testing (IVRT) of Topical Hydrocortisone Acetate Creams: a novel approach using positive and negative controls

  • Authors: Mudyahoto, Nyengeterai Amanda , Rath, Seeprarani , Ramanah, Ashmita , Kanfer, Isadore
  • Date: 2020
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/149849 , vital:38888 , dx.doi.org/10.14227/DT270120P6
  • Description: The objective was to develop and validate an in vitro release testing (IVRT) method to assess the release of hydrocortisone acetate (HCA) from five topical formulations. A marketed generic cream containing 1% HCA was used as the reference product. Vertical diffusion cells (VDCs) were used to assess and compare the release rates of HCA from cream formulations containing 0.5%, 1%, and 1.5% HCA. The study describes a novel approach to test the discriminatory power by including both positive and negative controls to declare pharmaceutical equivalence or inequivalence. The validated method was found to be sensitive, linear, precise, reproducible, robust, and selective for the analysis of HCA from topical cream products. Equivalence or inequivalence was established based on SUPAC-SS acceptance criteria using a 90% CI with limits of 75–133.33%. The IVRT method was shown to have discriminatory ability to appropriately measure significant differences in drug release from various cream formulations. This approach also provides useful information for the future development of acceptable IVRT methods to assess topical dosage forms for local action containing different drugs.
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  • Date Issued: 2020

In Vitro Studies on Antioxidant and AntiParasitic Activities of Compounds Isolated from Rauvolfia caffra Sond

  • Authors: Tlhapi, Dorcas B , Ramaite, Isaiah D , Anokwuru, Chinedu P , van Ree, Teunis , Hoppe, Heinrich C
  • Date: 2020
  • Subjects: To be catalogued
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/425993 , vital:72305 , xlink:href="https://doi.org/10.3390/molecules25173781"
  • Description: As part of an ongoing study of natural products from local medicinal plants, the methanol extract of stem bark of Rauvolfia caffra Sond was investigated for biological activity. Column chromatography and preparative thin-layer chromatography were used to isolate lupeol (1), raucaffricine (2), N-methylsarpagine (3), and spegatrine (4). The crude extract, fractions and isolated compounds were tested for anti-oxidant, antitrypanosomal and anti-proliferation activities. Two fractions displayed high DPPH (2,2-diphenyl-1-picrylhydrazyl) free radical scavenging activity and reducing power with IC50 (The half maximal inhibitory concentration) and IC0.5 values of 0.022 ± 0.003 mg/mL and 0.036 ± 0.007 mg/mL, and 0.518 ± 0.044 mg/mL and 1.076 ± 0.136 mg/mL, respectively. Spegatrine (4) was identified as the main antioxidant compound in R. caffra with IC50 and IC0.5 values of 0.119 ± 0.067 mg/mL and 0.712 ± 0 mg/mL, respectively. One fraction displayed high antitrypanosomal activity with an IC50 value of 18.50 μg/mL. However, the major constituent of this fraction, raucaffricine (2), was not active. The crude extract, fractions and pure compounds did not display any cytotoxic effect at a concentration of 50 μg/mL against HeLa cells. This study shows directions for further in vitro studies on the antioxidant and antitrypanosomal activities of Rauvolfia caffra Sond.
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  • Date Issued: 2020

In vitro susceptibility of Staphylococcus aureus to porphyrin-silver mediated photodynamic antimicrobial chemotherapy

  • Authors: Shabangu, Samuel Malewa
  • Date: 2020
  • Subjects: Porphyrins , Nanoparticles , Photochemotherapy , Drug resistance in microorganisms , Staphylococcus aureus
  • Language: English
  • Type: text , Thesis , Masters , MSc
  • Identifier: http://hdl.handle.net/10962/167476 , vital:41484
  • Description: This work reports on the syntheses and characterization of symmetrical and unsymmetrical porphyrin complexes namely, 5,10,15,20-tetra(4-pyridyl)-porphyrinato zinc(II) (1), 5,10,15,20-tetrathienyl porphyrinato zinc(II) (2), 5-(4-hydroxyphenyl)-10, 15, 20-tris(2-thienyl) porphyrinato zinc(II) (3), 5-(4-carboxyphenyl)-10,15,20-tris(pentafluorophenyl)- porphyrinato zinc(II) (4), 5-(4-carboxyphenyl)-10,15,20-triphenyl-porphyrinato zinc(II) (5) and 5-(4-carboxyphenyl)-10, 15, 20-tris(2-thienyl)-porphyrinato zinc(II) (6). The synthesis of silver nanoparticles (AgNPs) was also undertaken in this research work. Complexes 1, 2, 3 and 6 were linked to oleic acid/oleylamine functionalized nanoparticles via self-assembly and 4-6 were linked via covalent interaction through an amide bond to glutathione capped AgNPs. The effect of nature of bond along with symmetry were investigated, of interest were the five membered thienyl substituents. The photophysical and photochemical behaviour of the complexes and their conjugates with AgNPs were investigated in dimethylformamide. The porphyrin and AgNPs conjugates afforded an increase in singlet oxygen quantum yield. Complexes 1-6 and their conjugates were used for photodynamic antimicrobial chemotherapy of Staphylococcus aureus. The antimicrobial studies were done in two different concentrations of 0.36 and 2.0 μg/mL. The thienyl substituted porphyrin complexes and their conjugates gave better photodynamic activity as compared to phenyl analogues
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  • Date Issued: 2020

Inclusion in organisations following disability

  • Authors: Durrheim, Zenita Beth
  • Date: 2020
  • Subjects: People with disabilities -- Employment -- South Africa
  • Language: English
  • Type: Thesis , Masters , MA
  • Identifier: http://hdl.handle.net/10948/47818 , vital:40380
  • Description: Given the prevalence of disability in South Africa and specifically amongst the working population, this study explores the experiences of individuals who have been rendered disabled following injury and have returned to work. This study used a qualitative research design, specifically from an interpretative perspective to gain an understanding of individuals’ experiences of inclusion in organisations following disability due to injury. The phenomenological approach was best suited to this study in terms of its provision of valuable data collection directly from the participants, based on their own unique experiences. The research methodology was based on a multiple case study approach. Semi-structured interviews were conducted with 11 identified participants through purposive sampling. Through thematic analysis, five themes of inclusion were identified including ‘supportive relationships’, ‘organisational support, accommodation and policies’, ‘nature of the working environment’, ‘work ability and financial implications’ and finally ‘personal well-being’. Furthermore, for each of the primary themes, 12 sub-themes were identified. These themes and sub-themes were explored in relation to participant experiences of inclusion as well as linking specific literature of inclusion, return-to-work and disability models to the themes presented. Linking the findings to existing theoretical models of inclusion provided context with many of the themes identified also evident within the theoretical models. The factors identified within the themes of inclusion were conceptualised at different systemic levels with eight factors identified at the macro-organisational level, nine factors at the meso-group level and eight factors at the micro-group level. These identified factors could aid organisations and policymakers to ensure the effective inclusion of individuals with disabilities in organisations.
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  • Date Issued: 2020

Incorporating geomorphic knowledge in the management of wetlands in Africa’s drylands: a rapid assessment of the Kafue Wetland

  • Authors: Lidzhegu, Zwidofhelangani , Ellery, William F N , Mantel, Sukhmani
  • Date: 2020
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/157108 , vital:40087 , https://doi.org/10.1007/s13157-019-01172-9
  • Description: Limited knowledge of wetland geomorphic processes often results in poor wetland management. This study aims to illustrate the importance of incorporating geomorphic knowledge of wetland origin in their management. The geomorphic origin and dynamics of the Kafue wetland were determined from the analysis of remotely sensed and geological data. The wetland is a remnant of a paleo-lake that was captured by the tributary of the middle Zambezi River. At the point of capture, resistant Muva Group metavolcanic rocks dominate narrow valleys characterised by straight channels. The resistant lithology prevents the lower Kafue River to cut into the wetland thus maintaining wetland conditions upstream. Sedimentation regime through overbank and bed deposits shaped the wetland’s structure, ecological diversity, and hydrological functioning. The operation of the Itezhi-tezhi dam has negatively impacted the wetland’s hydrological and sedimentological regime. The dam starves the system of sediment needed for promoting levee and channel bed aggradation. Regulated discharge with reduced sediment load can lead to channel incision and therefore reduce flood frequency, which may ultimately lead to wetland desiccation.
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  • Date Issued: 2020

Increasing temperatures increase the risk of reproductive failure in a near threatened alpine groundnesting bird, the Cape Rockjumper Chaetops frenatus:

  • Authors: Oswald, Krista N , Diener, Elizabeth F , Diener, John P , Cunningham, Susan J , Smit, Ben , Lee, Alan T K
  • Date: 2020
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/149324 , vital:38825 , https://0-doi.org.wam.seals.ac.za/10.1111/ibi.12846
  • Description: A major cause of reproductive failure in birds is nest predation. Predation risk depends on predator type, as predators vary in their ecology and sensory modalities (e.g. visual vs. olfactory). Snakes (generally olfactory predators) are a major nest predator for small birds, with predation strongly associated with higher temperatures. We investigated nest survival in a ground‐nesting alpine species, the Cape Rockjumper Chaetops frenatus , endemic to alpine fynbos in southwestern South Africa. We collected 3 years of nest data, testing whether nest survival was related to (1) habitat stage (early post‐fire vs. late post‐fire habitat, ≤ 3 and > 3 years since fire respectively), (2) nest concealment and (3) temperature. We found that nests had better survival at lower temperatures, with snake predation (our main source of predation) increasing in higher temperatures.
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  • Date Issued: 2020

Index of coordination for swimming and running in triathletes: a comparative study

  • Authors: Van Den Bergh, Katelyne Mei
  • Date: 2020
  • Subjects: Triathletes
  • Language: English
  • Type: Thesis , Masters , MA
  • Identifier: http://hdl.handle.net/10948/46406 , vital:39598
  • Description: The primary aim of this study was to compare the Index of Coordination (IdC) for both sprint and endurance swimming and running of less-skilled level triathletes. The researchutilised a quantitative approach, specifically exploratory, with a one group post-test-only research design. Twenty participants from the triathlon community, ages 18 years and older, were selected via purposive and convenient sampling. The participants were expected to complete a total of four physical tests, namely 50 m sprint swim, 1500 m endurance swim, 50 m sprint run,and 5000 m endurance run, on four separate days, over a period of two weeks. The data was collected by video recording each participant performing each of the four different tests andcoded frame-by-frame onDartfish Video Solution (10.0).The IdCwas derived by identifying the time-in markers and time-out markers for both left and right arms when swimming; and by identifying the time-on markers and time-off markers for both left and right legs when running. The results revealed significant differencesbetweenthe IdCvalues ofsprint swimming and endurance swimming(p<0.001); sprint running andendurance running(p<0.001); sprint swimming andsprint running(p<0.001); andendurance swimmingandendurance running(p<0.001).The top performersin each testwere significantly faster than bottom performers(sprint swimming: p<0.001; sprint running:p<0.001; endurance swimming: p<0.001; endurance running: p<0.001) but no significant group differences on associated IdC were found(sprint swimming: p=0.535; sprint running: p=0.857; endurance swimming: p=0.132; endurance running: p=0.775).Bothendurance tests were divided into three equal portions and it was found that 23% ofthe fastest trial endurance swim time can be explained by the IdC obtained in portion three(p=0.032); and that 62% of the fastest trial endurance run time can be explained by the IdC obtained in portion one(p<0.001). The overall findings of the study suggest that an IdC mode is considered efficient relative to the environmental contextand thatIdCis relative to skill level or alternatively independent of performance times. The IdC, therefore, remains inconclusive as an alternative method but warrants further investigation particularly in longer distance endurance events.
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  • Date Issued: 2020

Indigenous Knowledge on Birthing Practices and the Use of Uterotonic Medicinal Plants to Prevent and Treat Postpartum Haemorrhage: A Mixed Methods Approach

  • Authors: Kovane, Gaotswake Patience
  • Date: 2020
  • Subjects: Medicinal plants Uterine hemorrhage
  • Language: English
  • Type: Thesis , Doctoral , PhD (Nursing)
  • Identifier: http://hdl.handle.net/10353/11385 , vital:39067
  • Description: There is a dearth of publications on women’s use of TMPs during the perinatal period. (Nergard et al., 2015). It is recommended that “plants used by pregnant women need to be better known in order to ensure that pregnant women receive effective treatment, to identify potentially unsafe use, and also to preserve valuable information about medicinal plants for women’s reproductive health for the future” (Nergard et al., 2015). Tripathi, Stanton and Anderson (2013:16) conclude that “[f]urther research is needed on the uterotonic efficacy of traditional preparations and on interventions to address the use [of TMPs] during labour”. Gruber and O’Brien (2011:218) support the statement and argue that the search for a “novel cyclotide-producing plant…may eventually lead to the development of novel uterotonic …drugs”. Pharmacological evidence of TMPs may promote the safe use of TMPs by IKHs during birth and the postpartum period. Kaingu, Oduma and Kanui (2011:495) emphasized that TBAs still have a crucial role to play in society, by assisting labouring women in rural communities and their “knowledge on medicinal plants is equally important and should be preserved for posterity”.
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  • Date Issued: 2020

Individualism and collectivism as moderators of the relationship between achievement motivation and entrepreneurial interest among undergraduate students at Walter Sisulu University

  • Authors: Magadlela, Asanda Sinazo
  • Date: 2020
  • Subjects: Individualism -- Psychological aspects Collectivism -- Psychological aspects
  • Language: English
  • Type: Thesis , Doctoral , PhD
  • Identifier: http://hdl.handle.net/10353/18543 , vital:42607
  • Description: The purpose of this study” is “to explore individualism and collectivism” “as moderators of the relationship between entrepreneurial” interest “and achievement motivation”among undergraduate students. The study is focused on analysing the relationship behind the variables and what drives the University students of Walter Sisulu University towards the business development of young people. “Researchers have traditionally associated individualism with high rates of firm creation, arguing that an orientation towards achievement and the pursuit of personal objectives” (dominant aspects of individualist cultures) “are determinants of entrepreneurial activity.” “The current analysis shows that a culture correlates to entrepreneurship”, “but cannot uphold the idea that higher levels of individualism mean higher rates of entrepreneurship.” “Many universities have introduced entrepreneurship education to promote the interest” of undergraduates in “becoming future entrepreneurs. Here, the researcher tries to retrieve the undergraduate’s interest and achievement motivation which influences them to entrepreneurial intentions. Based on” the “literature” review, it identifies various factors that are used in the predictions of entrepreneurial interest. “These factors were” adopted “to explore” student’s interests. “Survey questionnaires were distributed to” two campuses from the University of Walter Sisulu, namely; College street campus (East London) and the Potsdam campus which is the main campus of the University. “A total of” 154 “valid data” was “analysed using multiple regressions. The results show that entrepreneurial” interest “was predicted by achievement” motivation, individualism and collectivism.
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  • Date Issued: 2020

Influence of intra-and interspecific variation in predator–prey body size ratios on trophic interaction strengths:

  • Authors: Cuthbert, Ross N , Wasserman, Ryan J , Dalu, Tatenda , Kaiser, Horst , Weyl, Olaf L F , Dick, Jaimie T A , Sentis, Arnaud , McCoy, Michael W , Alexander, Mhairi E
  • Date: 2020
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/149358 , vital:38839 , https://0-doi.org.wam.seals.ac.za/10.1002/ece3.6332
  • Description: Predation is a pervasive force that structures food webs and directly influences ecosystem functioning. The relative body sizes of predators and prey may be an important determinant of interaction strengths. However, studies quantifying the combined influence of intra‐ and interspecific variation in predator–prey body size ratios are lacking. We use a comparative functional response approach to examine interaction strengths between three size classes of invasive bluegill and largemouth bass toward three scaled size classes of their tilapia prey. We then quantify the influence of intra‐ and interspecific predator–prey body mass ratios on the scaling of attack rates and handling times.
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  • Date Issued: 2020

Influence of process energy on stress corrosion susceptibility of a friction hydro pillar repaired steam turbine rotor disc blade locating hole

  • Authors: Pentz, Willem Gerhard
  • Date: 2020
  • Subjects: Friction welding , Mechanical engineering
  • Language: English
  • Type: Thesis , Doctoral , DPhil
  • Identifier: http://hdl.handle.net/10948/47106 , vital:39810
  • Description: Currently the power generation industry is struggling to keep older coal power plants running efficiently. One of the major hurdles is to keep repair and service cost low. Over time stress corrosion cracking (SCC) occurs in the locating pinholes of tier type rotors which locate the turbine blades. This is where this research aims to assist with an alternative repair technique, Friction Hydro Pillar Processing (FHPP) welding, to have longer service intervals thus saving cost and time. The same material can be used for welding and a new aligned hole can be drilled. FHPP welding is a solid state friction welding process. Four different FHPP axial forces were selected to compare their respective performance in subsequent tensile testing, impact testing and SCC testing. All the tensile samples extracted from preheated welds and post weld heat treated welds fracture in the parent material, which indicates good weld efficiency. The impact crack route from the weld nugget towards the parent material was identified in the energy and force graph. Axial force which promote impact toughness can be selected with this curve. SCC occurs when a tensile stress is applied to a susceptible material when in a conducive environment for cracking. A new SCC W-shape was designed and performed well during initial testing. With the SCC W-shape two specimens can be extracted opposite each other and tested. Both the preheated weld samples and the post weld heat treatment (PWHT) weld samples had improved SCC performance over their respective parent material samples. A high axial force, low process energy, and high process energy rate (low process energy and low weld time) produced a weld with improved SCC resistance. FHPP (with PWHT) is a promising repair technique as it improved on the SCC resistance and impact toughness as well as having 100% bond efficiency. More research is still required to identify the SCC mechanism of the FHPP weld.
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  • Date Issued: 2020

Influence of Tamarix species on soil physicochemical properties and mapping its distribution and density using GIS in Western Cape, South Africa

  • Authors: Mlahlwa, Asiphe
  • Date: 2020
  • Subjects: Tamarisks
  • Language: English
  • Type: Thesis , Masters , MSc
  • Identifier: http://hdl.handle.net/10353/18588 , vital:42611
  • Description: Tamarix ramosissima invasion is unarguably one of the worst ecological disasters in South Africa and is classified under category 1b by the National Environmental Management: Biodiversity Act 2014 (NEM: BA). The exotic Tamarix species was introduced in South Africa during the early 1900s as an ornamental or phytoremediating plant. This study was conducted to assess Tamarix distribution and evaluate its impact on soil physicochemical properties in two sites at Leeu River and Olifant River in Western Cape, South Africa. Samples were collected from Leeu River (which consists both the exotic and native Tamarix species) and Olifant River (only exotic Tamarix species). Three transects were laid from the water point outwards, with exotic Tamarix invading the river bank (first transect), the control on the open land (second transect) and the native Tamarix at the far end of the study site (third transect) in Leeu River. In Olifant, transects were laid according to the degree of invasion, low Tamarix density transect was referred to as T1, the medium as T2 and the high density as T3. Soil samples from each transect were taken from three points, at three soil depths (0-10, 10-20 and 20-30 cm) during winter and summer. Soil physiochemical properties such as soil pH, electro-conductivity (EC), total nitrogen (TN), total carbon (TC), soil organic carbon (SOC), sodium (Na+ ), potassium (K+ ), Calcium (Ca2+), Magnesium (Mg2+), bulk density, soil texture and sodium adsorption ratio (SAR) were determined. Soil chemicals properties including EC, Na+ , SAR, K+ and Mg2+ were found significantly higher under the native and the exotic Tamarix species when compared to Tamarix free soils. In general, salinity of surface soils (0–10 cm) was greater than those in the deeper soils with 5.05 mS/cm and 4.73 mS/cm observed under exotic and native Tamarix species, respectively. High levels of EC, K+ , Ca2+, Na+ , SAR, TN, TC and SOC were observed under T3, followed by T2 with the lowest being recorded in T1 at 0-10 cm. Unlike the soil EC, the effect of Tamarix density on soil pH at 0-10 cm soil profile was not significant. Alterations of soil physicochemical properties were more pronounced under the high Tamarix density as compared to the low invasion. Increased in distance from the river was related to a higher density of the invasive species and also topography had a major role in the change of species density. An increase in Tamarix density, results in high leaf litter which in turn results in salinity and soil nutrient at 0-10 cm. Soil salinity was dramatically increased under Tamarix species. Tamarix species are capable of altering the soil properties making it conducive for their growth.
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  • Date Issued: 2020

Influence of the jobs fund on the unemployment rate in South Africa

  • Authors: Banzana, Lubabalo
  • Date: 2020
  • Subjects: Unemployment--South Africa
  • Language: English
  • Type: Thesis , Masters , MPhil
  • Identifier: http://hdl.handle.net/10948/47508 , vital:40119
  • Description: Since the dawn of its democracy, South Africa has experienced multiple changes in its key economic policy. These changes were meant to address the poverty, inequality, and unemployment in the country. The post-1994 years have seen economic policies change from the Reconstruction and Development Programme (RDP) in 1994 to the Growth, Employment and Redistribution framework (GEAR) in 1996. Then came the Accelerated and Shared Growth Initiative for South Africa (AsgiSA) in 2006 and, most recently, the New Growth Path (NGP) and the National Development Plan (NDP) in 2010 and 2013, respectively (Chibba and Luiz, 2011). Despite numerous efforts made to change economic policy throughout the years, South Africa is still faced with the challenge of a high unemployment rate. To manage this issue, the South African government has introduced several interventions, such as the creation of a Jobs Fund in 2011, which meant that an initial investment amount of R9 billion was contributed by the government towards the attainment of its objectives. The research methodology used in this study was quantitative and, more specifically, based on the descriptive method of research.The primary objective of the research was to investigate the influence and effectiveness of the Jobs Fund through its job creation and skills development initiatives that were mechanisms to reduce the unemployment rate. The research aimed to assess the success of the Fund thus far in providing funding towards sustainable job creation and long-term employment. In addition, the study analysed the Fund’s influence in reducing in unemployment. In answering the primary objective of the research, it was not entirely possible to measure the influence of the Jobs Fund on the unemployment rate in South Africa, as other key factors need to be taken into consideration when making such an assessment. This is highlighted by the fact that, even though close to R7 billion has already gradually been committed to job creation activities by the government since 2011, the unemployment rate has continued to grow. Therefore, a study of the influence of the Jobs Fund on the unemployment rate would need take into consideration other key factors that influence unemployment.
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  • Date Issued: 2020

Informal learning in local farming practices by rural women in the Lake Chilwa Basin, Malawi: towards coping and adaptation to climate variability and climate change

  • Authors: Mphepo, Gibson Yadunda
  • Date: 2020
  • Subjects: Women -- Non-formal education - Malawi , Non-formal education -- Malawi , Women -- Malawi -- Social conditions , Crops and climate -- Malawi , Agricultural extension work -- Government policy -- Malawi , Environmental education -- Malawi
  • Language: English
  • Type: text , Thesis , Doctoral , PhD
  • Identifier: http://hdl.handle.net/10962/167540 , vital:41490
  • Description: Evidence reveals that informal learning is a neglected research area, globally and nationally. Informal learning, like formal and non-formal learning, is context specific. In the case of my study, the context was in local maize cultivation and the associated local farming practices which are also neglected. Research has shown that rural women in Malawi are significant change agents in socio-economic sectors, yet they are heavily affected by inequality. For example, extreme weather events of droughts and floods in the Lake Chilwa Basin, disproportionately affect more women than men because of their traditional gendered roles such as home care. The complexity of the dualistic nature of being change agents and victims of injustices at the same time offers a catalytic opportunity for potentially transformative social learning for transformative adaptation. Against this backdrop, I conducted a study to investigate and expand informal learning processes to contribute to building the resilience of women and other community members in Domasi and Nsanama Extension Planning Areas (EPA) within the Lake Chilwa Basin. Specifically, the study answered the following question: “How do drought and inter-seasonal dry spells influence informal learning processes to enable transformation adaptation among rural women cultivating maize in the Lake Chilwa Basin, Malawi?” To address the question, the first stage was to review local farming practices and the associated informal learning processes in Malawi. I then used third generation Cultural Historical Activity Theory (CHAT) as an overarching theoretical framework to guide the subsequent research processes which were split into three main phases: mirror data collection for expansive learning, formative change laboratory workshops, and data analysis and reflection. CHAT is a theoretical framework that helps us comprehend and analyze the relationship between the human mind (i.e. what people think and feel) and activity (what people do). It is a formative and activist learning theory that posits learning as occurring through collective activities to meet or change a common object (Mukute and Lotz-Sisitka, 2012, p. 345). For Koszalka and Wu, 2001(p. 493), within a CHAT framework, knowledge is socially constructed by individual learners, building on existing historical experiences, within the learners’ context. To construct this knowledge, learners use technology or mediating tools, as Vygotsky (1978) calls them. To collect mirror data, I conducted focus group discussions, observation studies, and document analysis. I also conducted key informant interviews with selected extension workers responsible for the two case study sites. The hub of my research constituted change laboratory workshops to expand learning through four of the seven expansive learning actions, namely questioning, analysis, modeling and testing the model. One of the essential procedures I relied on to expand learning during these change laboratory workshops was identification and analysis of contradictions that were mirrored back to women. The use of contradictions as fertile ground for learning is premised on Engstrom’s arguments that contradictions form a catalyst for learning. Data were analysed using two approaches: layered and power relations. A layered analysis is a step-by-step process of understanding a situation from the lower to a higher level (mature stage). For my research, this meant understanding sequential learning from questioning (session 1 – lower level) to testing the model (session 8 – higher level). The second data analysis approach, power relations, relates to the Women Empowerment in Agriculture Index (WEAI), a measure of the degree of women empowerment, their agency and inclusion in farming (Ruth et al., 2013, p. 3). I used this type of power analysis tool because my research was agriculture based. Both data analysis approaches relied on N-vivo which is a form of computer-based qualitative data management software. The software was ideal for my study which was also mostly qualitative. During phase 1 of data collection, I identified five local farming practices associated with local maize cultivation, a focus of my study. These practices were slash and burn (mphanje); traditional insect pest control measures; soil fertility enhancement techniques through kuojeka (crop residue incorporation) and livestock manure; traditional weather forecasts; and multiple cropping (mixed and sequential cropping). Among these, the most preferred by the women I interacted with were kuojeka, livestock manure and mixed cropping. I discovered that these local farming practices are informally learned mainly through word of mouth, observation, trials, women-dominated social networks and drama. I also discovered that some of these informal learning pathways are catalyzed by drought and dry spells. For example, during the 1949 and 2002 drought periods, women reported that they had learned new types of coping strategies such as the use of sawdust and banana root flour in place of maize flour to prepare nsima, a staple food in Malawi. During phase 2, change laboratory workshops, I identified 19 contradictions associated with local farming practices, most of which were related to the Government of Malawi bias towards modern farming practices such as hybrids. Other contradictions were related to traditional structures and norms and religion and traditional beliefs. Solutions were suggested for each of the contradictions. Some of these solutions were tested for their workability. These included setting up diversity blocks (demonstration plots) for local maize cultivation under irrigation and engagement of the youth through WhatsApp groups for the first time at the study sites. The results of the tests show that there is potential to transform local farming practices at the study sites and build social resilience against drought and dry spells. For example, from a local maize demonstration plot in Nsanama Extension Planning Area (EPA), farmers learned that kafula local maize is fast maturing and therefore cushions them against hunger as they wait for the main harvest in later months. Eighty-eight households shared local maize seed harvested from the demonstration gardens for upscaling. The Head of Nsanama EPA had also set up another demonstration garden in 2018-2019 growing season consisting of kafula at Nsanama EPA Headquarters for further informal learning purposes. This research has contributed new knowledge to the existing knowledge base about local farming practices and informal learning. These contributions are in the form of methods I used as well as results obtained. Among the key highlights of my contribution to the knowledge base is the development of scenarios as double stimulation tools for the emerging local farming activity system which emanates from the new model solutions resulting from change laboratory workshops. To the best of my knowledge, this was the first time rural communities were engaged in scenario development in Malawi. The first scenarios of this type were developed in 2010 for the Malawi State of Environment and Outlook Report and the process involved middle to senior managers of various institutions in Malawi. Through historical analysis, my research identified local crops that existed in the past but which are currently non-existent or rare. My study also identified unique local farming practices that even puzzled professionals, including the use of ripe banana peels of makumbuka and sukari to eradicate nansongole grass and native bamboos respectively. Both plant species are considered a nuisance in that they colonize land for cultivation. A breakthrough for radical transformation of local farming practices via informal learning requires development and review of relevant policies in Malawi. Such a process requires evidence. This research has provided background information for this process. For those policies already developed, this research has provided information that can help guide implementation of the generalized list of activities outlined in implementation plans of the respective policies.
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  • Date Issued: 2020

Information needs and information-seeking behaviour of practising medical doctors at Katutura and Windhoek central state hospitals in Namibia

  • Authors: Matsveru, David
  • Date: 2020
  • Subjects: Information behavior Information resources
  • Language: English
  • Type: Thesis , Doctoral , PhD
  • Identifier: http://hdl.handle.net/10353/17976 , vital:42000
  • Description: This study investigated the information needs and information-seeking behaviour of practising medical doctors at Katutura and Windhoek Central hospitals in Namibia. Anchored on Wilson’s (1996) model of information-seeking behaviour, the purpose of the study was to establish the information required by practising medical doctors to carry out their work, how they seek information, the information sources and resources they use, and the factors that affect them as they do so. Understanding users’ information needs and the way information is disseminated in hospitals is necessary in developing an effective information provision system and ensuring the quality of information services in the hospitals. A mixed-methods research approach was used to meet the objectives of the study. Questionnaires were administered on 140 practising medical doctors at Katutura and Windhoek Central state hospitals, while fifteen doctors were interviewed telephonically, using a semi-structured interview guide. IBM SPSS (Version 25) was used to analyse quantitative data from the questionnaires, while content analysis was used to analyse qualitative data from the interviews. The findings of this research are that practising medical doctors need information mainly for improving clinical decision-making, keeping up-to-date, improving professional knowledge, and continuing education. The study also revealed that medical doctors use a variety of information sources and resources. However, the degree to which information sources are xiii used depends on the clinical context (outpatients, wards and casualty/emergency). Some contextual factors (organisational context, socio-cultural context, and information sources) can either support or hinder doctors in seeking the information they need. The patient is one of the primary information sources for medical doctors. However, language problems are a significant challenge in communicating with patients or patients’ relatives. Lack of patients’ understanding of medical terms and unavailability of properly run libraries in hospitals are some of the factors that affect doctors’ information-seeking behaviour. Participants recommended health education for patients, training of medical doctors on the use of the Internet and ICT, provision of properly run hospital libraries, and improved communication with other international hospitals as some of the ways to improve health information sources and services. Three related models were drawn from the study’s findings, based on Wilson’s (1996) model and literature, namely, the doctors’ decision-making model (DDmM), the clinical context information sources model (CCISM), and the model of information needs and information-seeking behaviour of medical doctors (MINISBMD). The thesis concludes with practical recommendations to enhance the provision of information at Katutura and Windhoek Central hospitals and suggestions for further research.
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  • Date Issued: 2020

Ingqumbo yomthondo kukuzika kohlanga

  • Authors: Mtirara, Zodwa
  • Date: 2020
  • Subjects: Women and literature , Feminism and literature , Gender identity in literature , Masculinity in literature , Sex role in literature , Xhosa poetry , South African poetry (English) , Sex discrimination against women
  • Language: Xhosa, English
  • Type: text , Thesis , Masters , MA
  • Identifier: http://hdl.handle.net/10962/154095 , vital:39562
  • Description: Le yingqokelela yemibongo ebhentsisa ukutyeshelwa kobuntu nobuchule bamanina yinkolo yobuKrestu, kunye nenkolo yemveli okanye inkolo yesiNtu. Ikwenza oku ngokwaphula imithetho nemigaqo siseko yenkolo yobuKrestu nesiNtu sakwaXhosa malunga nokufanelekileyo ukuba owasetyhini akuthethe okanye akwenze. Ikwabhentsisa nokuhlukunyezwa kwabasetyhini, ibuza nemibuzo ngesimo esizifumana sikuso mva-nje. Ichukunyiswe bubomi bam kanye nobamanye amanina endiphila nawo ekuhlaleni. Ikubhentsisa ke oku ngokungenalusini njengoko imbongi uLesego Rampolokeng esenza. Izeka mzekweni ezibhalweni zooNtozakhe Shange, Diane Di Prima, Lidia Yuknavitch, noWame Molefhe. Iphikisa indlela ekubhalwe ngayo ngamanina ngooMema nooJolobe, isenza oko uNontsizi Mgqwetho angazange ade afikelele ukukwenza njengombhali wasetyhini.
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  • Date Issued: 2020

Initiating biological control for Nymphaea mexicana zuccarini (Nymphaeaceae) in South Africa

  • Authors: Reid, Megan Kim
  • Date: 2020
  • Subjects: Nymphaea mexicana zuccarini -- Biological control -- South Africa , Nymphaeaceae -- Biological control -- South Africa , Invasive plants -- Biological control -- South Africa
  • Language: English
  • Type: text , Thesis , Masters , MSc
  • Identifier: http://hdl.handle.net/10962/144510 , vital:38352
  • Description: Nymphaea mexicana Zuccarini (Nymphaeaceae) is an aquatic plant originating from south-eastern USA that is becoming increasingly invasive in South Africa as other invasive aquatic plants are being managed successfully through biological control. Mechanical and chemical control of aquatic weeds is expensive, damaging to the environment, and only effective in the short term, so biological control is more desirable as a management strategy for N. mexicana. The biological control of invasive alien plants requires that agents are host specific so that non-target risks are mitigated. For success to be achieved, it is important to ensure that the genetic structure of invasive populations is clarified so that agents can be collected from populations in the native range that match genetically to populations in the invasive range. This is especially important in cases where the morphology of invasive alien plants does not reflect genetic differences between populations. A previous study of the genetic structure of the invasive populations of N. mexicana in South Africa suggests the presence of hybrid forms of the plant in South Africa, with only one of these populations matching with samples from the native range. However, the study only used samples from two sites in the native range using amplified fragment length polymorphisms (AFLPs), so it was necessary to conduct further genetic analyses using samples from more sites in the native range. Hence, the first aim of this study was to develop a better understanding of the genetic structure of N. mexicana populations in the native and invaded range. Genetic samples were collected from sites in the native range during field surveys for potential biological control agents, and inter-simple sequence repeats (ISSRs) were used to compare the genetic structure of invasive and native populations of N. mexicana in South Africa. The results from these analyses suggest that seven of the 14 investigated invasive populations of N. mexicana in South Africa are genetically similar to populations in the native range, while the remaining seven populations are likely to be hybrid forms of the plant. This knowledge will be useful to target populations for biological control and highlights the need for further genetic analyses to determine the parentage of these hybrids so that biological control efforts are more likely to be successful. The initiation of a biological control programme requires that a series of steps are taken in order to maximise the likelihood that this form of intervention will be successful. The first few steps include: identification of the target weed and its genetic structure; exploration in the native range for potential biological control agents; and prioritisation of these agents based on factors such as climatic and genetic compatibility, feeding damage, abundance, and likely host range. Hence, the second aim of this study was to conduct surveys for potential biological control agents in the native range of N. mexicana, and to prioritise these agents. Field surveys were conducted between August and October in 2018 at 17 sites in Florida, Louisiana, and Texas, USA. Sites were selected based on climatic similarity of native sites compared to invasive sites by use of MaxEnt modelling. Native N. mexicana plants were searched for natural enemies, and these were prioritised based on feeding damage, abundance, incidence, and observations of field host range. Two species were prioritised: Bagous americanus LeConte (Coleoptera: Curculionidae) and Megamelus toddi Beamer (Hemiptera: Delphacidae). These species will be imported into quarantine facilities at Rhodes University for host specificity tests to be conducted. Understanding the factors that contribute to the successful establishment of biological control agents is important to improve the efficiency and reduce the costs incurred during the initiation of biological control programmes. Acquiring knowledge of the factors that predict the efficacy of biological control agents is similarly important, and these factors are discussed in the last chapter of this study. The challenges of the biological control of hybrids are also considered, and recommendations are made for the control of N. mexicana and other plants in South Africa.
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  • Date Issued: 2020

Innovative construction methods to address housing demand in South Africa

  • Authors: Tsosane, Mosa Brunette
  • Date: 2020
  • Subjects: Construction projects -- South Africa -- Management Housing -- South Africa
  • Language: English
  • Type: Thesis , Masters , MSBE
  • Identifier: http://hdl.handle.net/10948/49628 , vital:41742
  • Description: In South Africa, there is a prolonged waiting period for the needy to receive subsidy housing. Due to several factors contributing to this housing delivery delay, there is proliferation of informal settlements. The factors include fast-paced urbanization, which is mostly triggered by rural-urban migration that prompts urban growth and its attendant challenges that exert intense demands on the local government, thus the government is unable to keep up with the demands for housing and other related needs. The currently used conventional method (masonry construction) of construction for the construction of subsidy housing is perceived to be procedural and time consuming which is also one of the factors contributing to the delay in housing delivery. According to the research, interventions in the built form could be applied to address these issues. The focus of this study was on the construction aspect of the factors that contribute to the delay/problem. The primary aim for this study was to explore innovative prefabricated modular construction methods, proposed as alternatives to the construction of government subsidy housing in order to address housing demands in informal settlements. The research onion diagram was adopted and methodically followed as the research design for this study, whereby the data collection method that was adopted as part of the research onion was included a Desktop Survey and a Site Survey. The population and sample of this study comprised of a mixed group of participants, which were selected in accordance with the research attributes. The research findings indicate that the modular construction methods can indeed be used as an alternative to address some of the subsidy housing delivery problems. However, the challenge of any new innovative solution is to overcome end-user scepticism as resistance is inevitable. The research recommendation is for this research work to be taken to the next phase which would involve simulations of life size experimental models of these proposed innovative methods of construction, to further assess the viability of these proposed construction methods, before they may be implemented.
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  • Date Issued: 2020

Insect herbivores associated with Lycium ferocissimum (Solanaceae) in South Africa and their potential as biological control agents in Australia

  • Authors: Chari, Lenin D , Mauda, EV , Martin, Grant D , Raghu, S
  • Date: 2020
  • Subjects: To be catalogued
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/407035 , vital:70331 , xlink:href="https://hdl.handle.net/10520/EJC-203b8dbc7b"
  • Description: Lycium ferocissimum Miers (Solanaceae) is an indigenous shrub in South Africa but has become invasive in several countries including Australia, where chemical and mechanical control methods have proved costly and unsustainable. In Australia, biological control is being considered as a management option, but the herbivorous insects associated with the plant in its native range are not well known. The aim of this study was to survey the phytophagous insects associated with L. ferocissimum in South Africa and prioritise promising biological control agents. In South Africa, the plant occurs in two geographically distinct areas, the Eastern and Western Cape provinces. Surveys for phytophagous insects on L. ferocissimum were carried out repeatedly over a two-year period in these two regions. The number of insect species found in the Eastern Cape Province (55) was higher than that in the WesternCapeProvince (41), but insect diversity based on Shannon indices was highest in the Western Cape Province. Indicator species analysis revealed eight insect herbivore species driving the differences in the herbivore communities between the two provinces. Based on insect distribution, abundance, feeding preference and available literature, three species were prioritised as potential biological control agents. These include the leaf-chewing beetles Cassida distinguenda Spaeth (Chrysomelidae) and Cleta eckloni Mulsant (Coccinellidae) and the leaf-mining weevil Neoplatygaster serietuberculata Gyllenhal (Curculionidae).
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  • Date Issued: 2020
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