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The use of electronic information resources for course assignment by undergraduate students in the Faculty of Humanities at University of Limpopo
Get PDFThesis (M.INF.) -- University of Limpopo, 2023The study examined the use of EIRs for course assignments by undergraduate students in the Faculty of Humanities at the University of Limpopo, South Africa. The researcher adopted the survey method and a quantitative research approach. The tool employed for data collection was an online questionnaire from a sample population of 364 respondents. Questionnaires were sent to undergraduate students emails and out of 364, 234 responses were received, representing 64% of the total sample to whom the questionnaire was distributed. Data were analysed using SPSS V26 Windows and It was evident from the analysis that 216 (92%) of the respondents were aware of EIRs and had a positive attitude towards EIRs as they considered it “comfortable”. About 216 (92%) respondents were aware of EIRs but were not using them. The barriers endured by respondents when using EIRs were attributed to poor internet connectivity and a lack of skills (no trainings). Therefore, the study suggested that the library should improve its services on the provision of EIRs to ensure that students are satisfied with the availability and usefulness of EIRs and to improve internet connectivity. Furthermore, it was recommended that the librarians should establish more trainings and orientations for use of EIRs and compulsory e-learning classes for undergraduate students
Self-objectification and body dissatisfaction among the youth in Phalaborwa, Limpopo Province
Get PDFThesis (M. A. (Clinical Psychology)) -University of Limpopo, 2022The prevalence and co-occurrence of self-objectification and body dissatisfaction have become a noteworthy concern the world over, breaking demographic and sociocultural barriers such race, age, gender, sexuality, socio-economic background, and education level. Self-surveillance has also been shown to prevail where self objectification and body dissatisfaction are concerned. However, there is limited research that investigates the role of cultural identity in the relationship between these phenomena. This study investigated how self-objectification interrelates with self-surveillance and body dissatisfaction within a sample of 168 participants, comprising of youth aged between 14 and 24. More importantly, the study investigated the mediational role of self-surveillance and cultural identity in the relationship between self-objectification and body dissatisfaction. This cross sectional, quantitative study showed that neither self-surveillance nor cultural identity was shown to have any mediational effect on the relationship between self objectification and body dissatisfaction. Specifically, the indirect effects of SOBBSOP on Body dissatisfaction through both Self-surveillance and Cultural identity were not different to zero (CI = -.063 to .077 and -.064 to .086, respectively); and, the indirect effects of Self-objectification on Body dissatisfaction through both Self surveillance and Cultural identity were not different to zero (CI = -.040 to .072 and .077 to .066, respectively). As such, the results failed to support the predictions of the present study. It is recommended that future studies on the topic should focus on increasing sample size. Also, it is necessary to validate the scales for use in an African context, and rule out the possibility that lack of scale validation may have contributed to the outcomes
Insurance fraud detection using extreme gradient boosting and random forest algorithms
Get PDFThesis (M.Sc. (e-Science)) -- University of Limpopo, 2023The rising amount of fraud in claims has been of great concern to the insurance companies. In this research work, we developed two machine learning models namely, Extreme Gradient Boosting (XGBoost) and Random Forest for the purpose of insurance fraud detection based on auto insurance claims data. The models detect fraudulent claims and classify them into fraudulent or non-fraudulent. Different data pre-processing techniques are used to clean, explore, and extract relevant features. The effectiveness of the algorithms are observed using performance evaluation metrics: precision, recall and f1 score and confusion matrix. We also introduced the Synthetic Minority Oversampling (SMOTE) and Random Oversampling (ROS) data augmentation techniques to handle the imbalanced data and compare the results of the models before and after the data is balanced. The comparative results of classification algorithms conclude that the XGBoost model is effective in fraud detection than the Random Forest model on imbalanced data. In addition to this, the Random Forest model was effective in predicting fraudulent claims when the data augmentation techniques were applied
Seed germination and seedling development of Jatropha Zeyheri :an indigenous tea plant in Limpopo Province of South Africa
Get PDFThesis (M.Sc. Agriculture (Horticulture)) -- University of Limpopo, 2023Indigenous teas are receiving much attention and global interest as a result of their nutraceutical and pharmaceutical benefits. Most of these tea plants are still collected from the wild and their domestication has become a necessity as a result of the rapid growth of the tea industry and increased global demands. However, like other indigenous plants, setbacks exist in the successful seed germination of wild tea plants on account of seed parasitism, low seed viability andgermination difficulties A study was undertaken to: (a) determine the effect of pre- treatments of Jatropha zeyheri seeds grown under laboratory conditions and (b) to evaluate growth and development of J. zeyheri seedlings under controlled conditions on different growth media. In the initial objective, matured seeds sourced from the wild were subjected to five (5) pre- treatments methods namely, clipping, piercing, de-coating, cold and hot water soaking. The sixth (6) untreated dry intact seeds served as reference. Treatments were organised in a completely randomised design (CRD) with 10 replications. Treated and untreated seeds were all placed on moistened filter-papers inside petri-dishes and incubated in a growing chamber at 27°C. At 21 days, data on mean germination time (MGT), germination rate (GR), germination index (GI) and germination percentage (GP) were collected and calculated, prior to analysis of variance (ANOVA). Fisher’ Least Significant Difference test was used to separate the means at 5% level of probability. In the subsequent objective, under greenhouse conditions, six (6) treatments namely, sand, sand + loam, loam + compost, loam + Hygromix, sand + compost, sand + Hygromix were used, while sand alone served as the reference medium. The treatments were arranged in a randomised complete block design (RCBD), replicated 10 times. Seeds were de-coated first and each seed was planted in 10 cm plastic pot, filled with the various growing media-mixtures at a depth of 2 cm and irrigated to field capacity. Data collected included seedling performance parameters, namely, MGT, GR, GI and GP as well as plant parameters namely, stem diameter (SD), chlorophyll content (CC), seedling length (SL), number of shoots (NS), dry shoot mass (DSM) and dry root mass (DRM) and were subjected to ANOVA. Fisher’ Least Significant Difference test was used to separate the means at 5% level of probability. Germination occurred at the reference and seeds treated with clipping and de-coating methods. Pierced, cold and hot-water soaked seeds failed to germinate. Treatments had significant (P≤0.05) effect on MGT, GP, GI and GR, contributing 57, 55, 51 and 55% to total treatment variation (TTV) in the respective variables. When compared with the intact seeds, MGT for the clipped seeds was at 3 days, whereas in the de-coated seeds it was in 7 days. The clipped seeds achieved 11% GP and 0.29 GI at a GR of 0.05. Noticeably, the de-coated seeds achieved highest (16%) GP and 0.3 GI at a GR of 0.08 when compared to the reference seeds. Treatments had significant (P≤0.05) effect on MGT, GP and GR of J. zeyheri seedlings, whereas no significant effects were observed on GI. Treatments contributed 25, 21, 9 and 22% to TTV in the respective variables. Relative to the reference medium, MGT for the de-coated J. zeyheri seeds sown on sand + compost occurred at 2 days, whereas emergence in sand + loam occurred at 7 days. The longest MGT (26 days) was observed in sand + Hygromix growing media. Germination percentage and GR for seeds sown on sand + compost was 1% and 1.1, whereas for seeds sown on sand + loam was 2% and 3.33E-03 and in seeds sown on sand + Hygromix, it was at 4% and 4.44E-03, respectively, when compared to the reference. In terms of plant parameters, treatments had no significant (P≥0.05) effect on SD, CC, SL, NS, DSM and DRM of J. zeyheri plantlets. In conclusion, the de-coating pre- treatment proved to be a better method for improving germination in seeds of J. zeyheri tea plant and the same de-coated seeds sown on sand + Hygromix achieved better emergence and development, proving that the growing media used was suitable to provide optimum germination and seedling developmentNational Research Foundation (NRF) and Agricultural Sector
Education and Training Authority (AgriSETA
Development of machine learning models for predicting properties of sodium-ion battery materials
Get PDFThesis (M.Sc.(Physics)) -- University of Limpopo, 2023In this work, machine learning regression techniques are applied to a large amount of data from Materials Project Database, to develop machine learning models capable of accurately predicting the properties of sodium-ion battery cathode materials. Different machine learning models, namely, Bayesian ridge, gradient boosting regressor, light gradient boosting machine, extra trees regressor, random forest, and orthogonal matching pursuit are successfully developed and validated, using SIB materials’ properties calculated from DFT as input dataset, with the models’ efficiency based on elemental properties of materials constituents feature vectors.
The target properties in this work include formation energy, final energy, Fermi energy, energy above hull, density, and band gap. The importance of feature vectors derived from the properties of materials’ chemical compounds and elemental properties of their constituent is evaluated. The average covalent radius and the average single bond covalent radius were found to be the most important descriptors in predicting formation and final energies, whilst the estimated face centred cubic lattice parameter, the average electronegativity, and the average density to be the most important descriptors for predicting the Fermi energy. The optimal features in predicting energy above hull were found to be the sum of sound velocity, sum of total unfilled electron, and the average ground state energy. Furthermore, the results show that maximum mass specific heat capacity and variance of density functional theory energy per atom descriptors are the most essential in accurately predicting the materials density and valence electron in d shell, the average radius and the average electronegativity been the most important features for predicting band gap.
Amongst various algorithms that are evaluated, the Bayesian ridge model is found to be the best model in predicting the formation energy with an accuracy of 0.99 and 0.01 eV coefficient of determination and mean square error, respectively, and final energy of 0.98 and 0.03 eV accuracy for the coefficient of determination and mean square error, respectively. Light gradient boosting machine model is found to be the best model in predicting the Fermi energy with an accuracy of 0.82 and 0.52 eV coefficient of determination and mean square error, respectively, and energy above hull of 0.67 and 0.01 eV, for the coefficient of determination and mean square error, respectively Extra trees regressor is found to be the best model in predicting the density with an accuracy of 0.95 and 0.09 g/cm3 coefficient of determination and mean square error, respectively, and band gap of 0.78 and 0.66 eV, for the coefficient of determination and mean square error, respectively. The models demonstrate an improvement accuracy in predicting the sodium-ion battery materials properties as demonstrated by the regression scores.Department of Science and Innovation-Interbursary Support (IBS
Efficient design towards highly selective low/self-powered gas sensor
Get PDFThesis (M.Sc.(Physics)) -- University of Limpopo, 2023The daily population activities linked to the emission of various hazardous gases that can be toxic, explosive, and flammable such as CO, H2S, SO2, NOx, CO2, and volatile organic compounds have a negative impact on human lives and the environment. The development of NO2 and CO gas sensors is vital for prompt detection due to their poisonous behaviour, which may lead to immediate deaths.
Consequently, tin dioxide (SnO2) and vanadium pentoxide (V2O5) nanostructures were prepared following a facile hydrothermal method using different bases for the detection of various gases. The SnO2-NaOH displayed hollow sphere-like structures with etched surfaces, while the SnO2-NH4OH and SnO2-Urea illustrated nanoflakes and hierarchically arranged nanoflakes forming spheres, respectively. The V2O5 nanostructures showed nanorod like structures that varied in thickness and length with base. Structural findings exhibited improved crystalline structure of the SnO2 in the following behaviour: SnO2-NaOH<SnO2-Urea<SnO2-NH4OH. In-situ electron paramagnetic resonance and photoluminescence studies disclosed that the SnO2-NaOH possessed a significantly high concentration of oxygen vacancies (VO). Consequently, the SnO2-NaOH based sensor disclosed an exceptional selectivity to CO gas amid other target gases while operating at low temperature (75 °C). The sensor displayed a higher resistance ratio (≈32) at 60 ppm, a sensitivity of 0.49 ppm-1, and a low theoretical detection limit of 70 ppb. Such unprecedented performance towards CO was owing to a higher number of surface defects induced by the strategy of utilizing NaOH as a base to tailor the surface properties of the SnO2SnO2/CuO-(1.0:1.0 M), SnO2/CuO-(0.5:1.0 M) and SnO2/CuO-(1.0:0.5 M) heterostructures-based sensors were also fabricated for detection of NO2 gas at room temperature. The fabricated materials were characterized using various techniques, to investigate the structure, morphology, internal structure, and optical properties. The elemental mapping was also carried out to investigate the distribution of both Cu and Sn. To test their suitability in gas sensing applications, the nanomaterials were tested towards various gases at different temperatures. Among the tested sensors, the SnO2/CuO-(1.0:1.0 M)-based sensor showed a higher response towards NO2, in the presence of other four gases at room temperature. At 100 C, the sensors showed a poor response, justifying that their optimal temperature is 25 C. These results indicate that these sensors could be considered as low-power consumption sensors for the detection of NO2.Council for Scientific and Industrial Research (CSIR
The portrayal of women by selected Xitsonga music composers
Get PDFThesis (Ph.D. (Xitsonga)) -- University of Limpopo, 2023The title of this study is “The portrayal of women by selected Xitsonga music
composers”. The main problem of this study is the gender stereotyping of women
by Xitsonga music composers. According to Neidhart and Carling (2003:08),
women’s identities and roles have traditionally been associated with weaknesses,
poor intelligence, laziness and lack of credibility. The purpose of this study is to
analyse the way women are portrayed by Xitsonga music composers in their
songs. The sample of this study comprised of 7 songs by Dr. Thomas Hasani
Chauke and Shinyori Sisters, 4 from George Maluleke and Van’wanati Sisters, 7
from Solly Makamu, 2 from Oscar Makamu, 3 from General Muzka, 3 from Eckson
Maluleke, 3 from Dr. Joe Shirimani and 3 from Benny Mayengani. The identification
of the selected composers from the different eras was purposively done to reveal
the fact that even in an era of democracy, where people are supposed to be
treated equally and live peacefully, stereotypes still persist in different
communities. The songs will be analysed to identify their themes and how women
are portrayed in the selected song lyrics. In this study, a qualitative research
design will be used by the researcher, to explore the portrayal of women in 32
selected Xitsonga songs. This study is foregrounded in the Feminist literary theory
and Psychoanalysis Theory. The analyses also revealed biasness in the manner in
which women were portrayed. A reflection of women stereotypes was observed
where women were portrayed as gold-diggers, untrustworthy, greedy, bullies,
prostitutes, immoral, trouble-makers and betrayers. This study recommends that
the perception of women and men should be equal
Determination of normal testicular development in tropical adapted South African Beef Bulls during phase C (centralised testing centre)
Get PDFThesis (M.Sc. Agriculture (Animal Production)) -- University of Limpopo, 2023Bull fertility is considered the most important consideration in the herd because bulls are responsible for conception across several females. There is a high correlation between scrotal circumference and fertility in bulls, and the bigger the better. However, there is a lack of information on the normal testicular development in tropical adapted beef bulls in South African. Therefore, a study was conducted to determine the normal testicular development by age and breed in tropical adapted South African beef bulls enrolled with the INTERGIS during Phase C testing. The recorded data was sourced from the ARC and analysed using the International Business Machines (IBM) Statistical Package for the Social Sciences (SPSS), version 25. The study used thirteen beef breeds namely; Angus SA, Afrikaner, Beefmaster, Bonsmara, Brahman, Charolais, Drakensberger, Hereford, Nguni, Limousin, Santa Gertrudis, Simmental, and Sussex. The bulls were between the ages of 150 and 250 days when admitted to Phase C with a testing length of 270 days. Analysis of variance (ANOVA) and Pearson’s correlation were used for data analysis. ANOVA results indicated that the Simmental bulls had the highest SC (36.00 cm) while the Brahman bulls had the lowest SC (30.00 cm). The results also showed a significant difference (P0.05) cattle breeds
The experiences of learner nurses regarding clinical placement during the coronavirus disease 2019 pandemic at the University of Limpopo
Get PDFThesis (M.A. (Nursing)) -- University of Limpopo, 2023Academic nursing programme during the COVID-19 pandemic has been affected, as
students had to be withdrawn from clinical experiential learning. This led to learner
nurses having challenges in completing their clinical hours required by the South
African Nursing Council training requirements. The study aimed to explore and
describe the challenges experienced by learner nurses regarding clinical placement
during the COVID-19 pandemic at the University of Limpopo.
Method: A qualitative, descriptive, and explorative research method was used to
explore the experiences of learner nurses regarding clinical placement during the
COVID-19 pandemic at the University of Limpopo. A non-probability purposive
sampling method was used to select participants. The population included 204
undergraduate learner nurses enrolled at the University of Limpopo to study Bachelor
of Nursing degree for the academic year 2021. Data was collected through focus group
interviews which consisted of eight to twelve learner nurses in each group. Six focus
group interviews were conducted to collect data. Data were analyzed following
Tesch`s open coding method. The measures to ensure trustworthiness namely
credibility, transferability, confirmability, and dependability were followed.
Results: The following themes emerged during data analysis; The impact of COVID19 on the clinical placement of learner nurses, restricted exposure to the clinical area
during a hard lockdown, the effects of COVID-19 on the mental well-being of learner
nurses and the learner nurses’ support, and recommendations. Additionally, the
following sub-themes also emerged during data analysis; Incompetence in the
performance of some skills, compromised integration of theory to practice, Inadequate
clinical hours as required by SANC, lack of personal protective clothing at the clinical
areas, exposure to COVID-19 risk, fear of COVID-19 Infection, fear of patients,
Inadequate support from preceptors, Inadequate supervision by the senior personnel
at the clinical area, difficulties to cope, personal and social coping strategies,
educational institution support for learner nurses, management of clinical learning and
clinical hours, preparation, protection, and support during clinical practice and the
provision of resources and compensation. Conclusion: Nursing education institutions should ensure that learner nurses get
clinical exposure even during a pandemic. The study further recommends that nursing
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education institutions procure good quality and sufficient personal protective
equipment for the learner nurses and that professional nurses at the accredited clinical
facilities should assist the learner nurses in correlating theory with practice during the
COVID-19 pandemic by supervising them during their clinical training.University of Limpop
Identification and characterisation of compounds with antimycobacterial activity from the leaves of Dombeya rotundifolia Hochs
Get PDFThesis (M.Sc. (Microbiology)) -- University of Limpopo, 2023Plants are not only an important source of medicines, but also play a significant role
in drug development for the treatment of diseases such as Tuberculosis (TB). TB is a
pulmonary disease that is caused by Mycobacterium tuberculosis complex. The aim
of the study is to identify and characterise antimycobacterial compounds from
Dombeya rotundifolia. The plant was collected from the University of Limpopo, dried
and ground into fine powder. Extraction was done using different solvents that differ
in polarity. The plant was screened and analysed for phytochemicals. Three major
phytochemicals were quantified using reagent assays and analysed using standard
curves. The antioxidant activity of the plant was determined using 2,2-Diphenyl-1-
picrylhydrazyl (DPPH) and ferric reducing power assay. The antibacterial activity of
the plant extracts was tested against Mycobacterium smegmatis using bioautography
and serial microplate broth dilution assay. The antibiofilm activity of the plant extracts
were evaluated using crystal violet assay. The anti-inflammatory activity of the plant
was determined using egg albumin protein denaturation assay. The cytotoxic effects
of the extracts were evaluated using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl
tetrazolium bromide (MTT) assay on THP-1 cell line. The antimycobacterial
compounds were isolated and purified using bioassay-guided assay incorporated with
column chromatography and preparative TLC. The isolated compounds were
analysed and identified using nuclear magnetic resonance spectroscopy (NMR). The
results obtained in this study showed that water was the best extractant, extracting
57.6 mg of the plant material, followed by methanol with 38.1 mg and hexane as the
least extractant with 12.4 mg. In the phytochemical analysis of TLC plates, there was
a separation of compounds in all the mobile systems, and a clear separation of
compounds was observed in the BEA mobile system, followed by the EMW system.
The plant has all major phytochemicals that are needed for drug development. The
plant extracts had antioxidant activity, which was confirmed by the quantitative assays.
The high inhibitory activity of the extracts was indicated by low MIC values that
inhibited the bacterial growth. The butanol extract had the lowest MIC value (0.13
mg/mL). The plant extracts were able to prevent the formation of biofilm at different
concentrations. The plant was proven to have anti-inflammatory properties by having
a high inhibition capacity to prevent protein denaturation. The cytotoxicity results
showed that the plant was toxic to the cells. The isolated antimycobacterial
compounds were identified as Eicosanoic acid and Docosanoic. They have moderate
activity with the MIC value of 0.25 mg/mL. The study indicated that the isolated
compounds have antimycobacterial activity, which showed that the plant has a
potential to treat TB or symptoms related to TB. However, further studies are needed
to evaluate their toxic effects before use.The National Research Foundation (NRF