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Antecedents of psychological well-being among workers within small and medium enterprises
No full textOrientation: In the contemporary business environment, employee mental health is neglected,
especially in mental health research and practice in African Small and Medium-sized Enterprises (SMEs). This occurs even though this sector is the largest contributor to developed economies. This study highlights the importance of psychological well-being in SME performance and the individual employee.
Research purpose: To investigate the influence of perceived organisational support, career goal development and empowering leadership on the psychological well-being of SME employees in Gauteng province, South Africa.
Motivation for the study: Despite increasing research on SMEs, few studies have investigated the impact of perceived organisational support, career goal development, and empowering leadership on psychological well-being in a Southern African context.
Research approach/design and method: This study followed a quantitative approach, using the survey methodology where a structured questionnaire was administered to 250 SME employees. To evaluate the psychometric properties of measurement scales, a confirmatory factor analysis was performed. Structural equation modelling was used to test the hypotheses.
Main findings: Perceived organisational support, career goal development and empowering leadership have a positive and significant impact on the psychological well-being of SME workers. A robust, positive and significant relationship exists between empowering leadership and psychological well-being.
Practical/managerial implications: The results indicate that SME managers in South Africa should pay more attention to, or place greater emphasis on, supporting employees in their organisations, recognising and assisting them in achieving their goals, and empowering them to be happy at work. If the psychological well-being of employees is prioritised, SME business performance will ultimately improve.
Contribution/value-add: This study contributes to the current body of Africa’s industrial psychology and mental health literature – a field that has received little research attention in developing countries like South Africa.Publisher's versio
Synthesis and characterization of bismuth doped strontium oxide powder and thin films
No full textThe main aim of this project was to investigate the synthesis and characterization of bismuth-doped strontium oxide powder and thin films. Firstly the luminescent properties and stability under electron beam irradiation of the SrO:Bi3+ phosphor powder were investigated and secondly the luminescent properties of SrO:Bi3+ thin films prepared by different techniques were studied. The luminescence from Bi3+ ions can be useful in obtaining blue to red emitting phosphors by using different hosts, when excited by ultraviolet (UV) light due to efficient conversion to longer wavelengths. The energy levels of Bi3+ ions are host dependent. Bi3+ is a low cost activator, which provide strong absorption of UV light and can be efficiently converted to longer wavelengths. These emissions are related to the 3P1 – 1S0 or 1P1 – 1S0 transitions of Bi3+ ions, which are strongly dependent on the host. The alkali-earth oxide phosphors offer a potential low-cost alternative to lanthanide-based blue phosphors. Bi3+ doped strontium oxide (SrO:Bi) phosphor powders were synthesized by the sol-gel combustion method using metal nitrates as precursors and citric acid as fuel.
A wide range of temperatures (800 - 1200 °C) and concentrations of Bi3+ (0.05 - 0.7 mol%) were used to determine the optimum sample annealing temperature and Bi3+ concentration. The optimum doping concentration, for a fixed annealing temperature of 1200 °C (2 h), was found to be 0.2 mol% and a further increase in the Bi3+concentration resulted in concentration quenching. Samples of this concentration were annealed at various temperatures and the optimum annealing temperature was found to be 1100 °C (2 h). The X-ray diffraction patterns (XRD) corresponded with the well-known face-centered cubic structure of SrO after high-temperature annealing that ranged between 1100 °C up to 1200 °C. Below 1100 °C strontium hydroxide peaks were also present. Williamson-Hall plots showed that the crystallite size was in the range of ~180 nm. Diffuse reflectance measurements of the pure host material showed it was strongly reflecting (~100%) down to a wavelength of about 230 nm, but when doped with Bi3+ an absorption band at 275 nm was observed that increased with increasing Bi3+ concentration. Scanning electron microscopy (SEM) revealed a cubic morphology and the grain size increased with annealing temperature.
Photoluminescence (PL) measurements indicated that the phosphor exhibited efficient blue emission around 445 nm under UV excitation, which also occurred for electron irradiation, but slightly shifted about 5 nm to a longer wavelength. PL results showed that the emission intensity did increase with an increase in the annealing temperature up to 1100 °C. The increased intensities were attributed to two factors. The first one is due to a combination of the decrease of the Sr(OH)2, and the second one segregation/diffusion of the Bi3+ ions from the bulk to populate the surfaces of the particles with a consequent loss in Bi3+ due to volatile species as a result of the increased annealing temperature. The intensity increased up to 1100 °C due to a decrease in the hydroxyl concentration and thereafter at higher temperatures resulted in a Bi3+ deficiency from the sample’s surface and therefore leading to a decrease in the dopant concentration. Auger electron spectroscopy (AES) was employed to analyze the surface chemical composition of the powder after pumping to a vacuum pressure of 2.6 × 10−8 Torr and back-filling the vacuum system with O2 to a pressure of 1.0 × 10−7 Torr. The presence of all major elements of SrO, namely Sr and O were confirmed, but Bi3+ was not observed due to its low concentration. Cl and C were also detected as contaminations on the surface. X-ray photoelectron spectroscopy (XPS) results for the Sr1-xO:Bix=0.002 sample also indicated the presence of the major components Sr and O of this material and some contaminations on the surface. By simultaneous monitoring of the cathodoluminescence (CL) and AES peak-to-peak heights over time for 22 h, the CL degradation of the phosphor was investigated. The slight decrease of the CL intensity (less than 20%) was due to the removal of C from the surface due to the electron stimulated surface chemical reactions (ESSCRs) which took place during electron bombardment. During the ESSCR process, the electron beam dissociates the O2 and other background species such as H2O to atomic species which subsequently react with C to form volatile compounds (COX, CH4, etc.). The CL intensity reduced slightly more and at a higher rate in the O2 back-filled environment than in vacuum during the degradation studies, due to the reaction of O2 with the adventitious C at a higher rate to form volatile compounds on the surface of the irradiated sample. The SrO was found to be stable under electron irradiation. XPS results indicated surface contaminated elements were completely removed after degradation.
An important application for phosphors is to make thin films for devices such as plasma displays and light emitting diodes. Sr1-xO:Bix=0.002 phosphor thin films were prepared by spin coating and pulsed laser deposition (PLD). Spin coating samples were obtained by sequentially depositing 10 layers at 3000 rpm for 30 s and then annealed at various substrate temperatures. The optimum annealing temperature was found to be 900 °C (2 h). For all thin films samples, XRD showed the thin film had a strong (111) preferential orientation on the cubic phase. The results imply that the crystallite size of the sol–gel-derived films increased slightly with the increasing annealing temperatures. The morphology of the samples was determined by SEM and atomic force microscopy (AFM). The main PL emission peak position of the thin films prepared by spin coating showed a shift to shorter wavelengths at 430 nm, if compared to the main PL peak position of the powder at 445 nm. Thin films were prepared by PLD of Sr1-xO:Bix=0.002 phosphor optimized for blue luminescence. The powder was pressed into a PLD target, which was annealed at 200 °C for 2 h in air to remove all adventitious water containing species. Thin films were then successfully fabricated by PLD in vacuum or an O2 working atmosphere on Si (100) substrates. Films were deposited using different types of excimer lasers namely a KrF laser (248 nm) with energy 300 mJ/pulse and a ArF laser (193 nm) with energy 150 mJ/pulse with the constant substrate temperature at 300 °C and deposited at different substrate temperatures using a Nd:YAG laser (266 nm) with energy 33.3 mJ/pulse. The microstructures and PL of these films were found to be highly dependent on the substrate temperature. XRD of the thin films obtained with the different types of excimer lasers showed the thin films also had a strong (111) preferential orientation on the cubic phase. XRD of the films deposited using the Nd:YAG laser in O2 showed that the crystallinity increased with an increase in the substrate temperature, changing from amorphous to a cubic structure. At the highest temperature of 500 °C, the 111 and 200 SrO peaks were almost the same height, as in the powder. However, for 350 °C and 200 °C, the 200 peak was much smaller, which suggests some preferential orientation for films prepared at lower substrate temperatures. All films deposited in vacuum were amorphous. All the SEM images show a very rough thin film surface that comprises of rounded irregular particles of different sizes and shapes, which were not uniformly distributed and which do not seem to be highly dependent on the substrate temperature. AFM results showed that the surface roughness decreased as the substrate temperature increased. The optimum substrate temperatures for the maximum luminescence (both (PL) and (CL)) were 200 °C and 50 °C for deposition in O2 and vacuum, respectively. The main PL emission peak position of all the PLD thin films showed a shift to shorter wavelengths at 427 nm, when compared to the powder (445 nm). The optical properties of the powder and thin films showed different results because the Bi3+ ion is very sensitive towards its environment. Time of flight secondary ion mass spectroscopy (ToF SIMS) depth profiles for the samples deposited in O2 or vacuum at different substrate temperatures look similar, except for a slight thickness variation. The PLD fabrication technique is suggested to be the best technique to fabricate the SrO:Bi3+ phosphor thin films.South African Research Chairs Initiative (SARChI)African Laser Center (ALC)University of the Free Stat
Drug interactions between HIV-associated lymphoma treatment and antiretroviral therapy
No full textDespite the large-scale roll-out of ART in the mid-1990s, HIV and HIV-associated diseases remain a major health problem in South Africa. HIV-associated lymphoma contributes significantly to the morbidity and mortality of the HIV-positive population. The majority of HIV associated lymphomas are diffuse large B cell lymphomas (DLBCL), which have been reported to occur 60 to 200 times more commonly in patients with HIV than in the general population. Drug interactions are inevitable when treating HIV-associated lymphoma and can alter the efficacy of treatment and ultimately patient outcomes. Therapeutic questions have been raised pertaining to the need to find a balance between the administration of effective cytotoxic treatment and the effect it has on immune function. Complications such as infections and chemotherapeutic toxicity can occur. Dosing schedules may need to be adapted and certain combinations may be prohibited. The aim of this study was to conduct a critical overview of drug interactions between antiretroviral therapy used in the treatment of HIV and antineoplastic drugs used in the treatment of HIV-associated lymphoma. The purpose was to develop a quick reference tool to serve as a guide for clinicians to assist in identifying important drug interactions. Known drug interactions between 19 antiretroviral drugs and 13 antineoplastic agents used in the treatment of HIV and HIV-associated lymphoma respectively were investigated. Standard antiretroviral therapy (ART) regimens proposed by the national protocol were compared to drugs used in the following antineoplastic regimens: ABVD, CODOX-M-IVAC, CALGB9251, hyper- CVAD, dose adjusted R-EPOCH and R-CHOP. Data were obtained during March and April 2019 from three different internet-based drug interaction checkers, namely Medscape Drug Interaction Checker (https://reference.medscape.com/drug-interactionchecker), Lexicomp Online (https://www.wolterskluwercdi.com/lexicomp-online/) and RxList (https://www.rxlist.com/druginteraction-checker.htm). Interactions were classified as not clinically significant, no interaction, decreased or increased effect, contraindicated, increased toxicity, increased toxicity of both drugs due to synergism and loss of virological response. In total, 117 drug interactions were identified, of which 105 were deemed clinically significant. No interactions were found when the nucleoside reverse transcriptase inhibitors (NRTIs) lamivudine, abacavir and emtricitabine were used. The integrase inhibitors raltegravir and dolutegravir and the fusion inhibitor enfuvirtide also had no documented drug interactions. Chemotherapeutic agents that were found to have no significant drug reactions include cytarabine, rituximab and dacarbazine. Important drug interactions between the non- nucleoside reverse transcriptase inhibitors (NNRTIs) tenofovir and zidovudine and antineoplastic drugs were noted. Toxicity of tenofovir may be increased with concomitant use of bleomycin and ifosfomide. Caution must be taken when using zidovudine in combination with methotrexate, ifosfamide, vincristine and vinblastine, as the toxicity of both drugs is increased when used in combination. Efavirenz, a NNRTI, was found to have many interactions with antineoplastic drugs, the most significant being decreased levels of doxorubicin. Many drug interactions were noted between protease inhibitors and antineoplastic drugs. Anthracycline-associated cardiomyopathy may be induced when used concurrently with protease inhibitors. In general, rilpivirine is known to have a good side-effect profile. However, it must be noted that when combined with dexamethasone, this combination may lead to a loss of virologic response. Other significant interactions with drugs not included as standard ART is discussed in the article. Tailoring drug therapy according to individuals' specific requirements and proper medication reconciliation is critical when treating patients with HIV-associated lymphomas. Clinicians need to be aware of important interactions between antiretroviral therapy and antineoplastic drugs. Therapeutic monitoring and close interaction between role-players in the management of these patients is crucial. Communication between the clinic issuing the antiretroviral therapy, the attending haematologist or oncologist and the patient is vital to continuity of care. A quick referencing tool was developed as a guide to clinicians involved in the treatment of HIV associated lymphoma
A strategy to improve formative assessment practice of financial literacy in economic and management sciences in a Grade 9 class
No full textClassroom-based assessment has a major role to play in the education of learners. Learners spend the best part of their young lives at school with their teachers, and it is through classroom assessments that their capabilities can be understood better. The study aimed to design a strategy to improve formative assessment practices of financial literacy of economic and management sciences in a Grade 9 class. Participatory action research was the research approach used to generate data. The data of the study was solicited from subject advisors, Grade 9 economic and management sciences teachers, student teachers, a district school-based assessment coordinator and a deputy principal responsible for curriculum, and economic and management sciences learners from different schools around Mangaung. Data generated through discussions during meetings and on WhatsApp groups was analysed using Van Dijk’s critical discourse analysis, by means of three levels of data analysis: textual, social and discursive. It was deduced from the findings that the success of the strategy is reliant on internal support, and the capabilities of the teachers. The study, therefore, recommends that careful teacher training is provided, and that teacher support is prioritised, so that they can implement correct formative assessment practices
Inclusive Maseru: a third space of community: exploring the current discourse in the Maseru city metropolis through the lens of thirdspace & thresholds of an Urban Music Academy
No full textThe thesis investigates a language of space that addresses the complexities of identity and culture in the architectural and urban planning discourse. Complexities that have long been at the heart of discussions relating to architectural form and inclusivity. From derivatives of the philosophy of Gilles Deleuze’s “FOLD” concept to theories of Edward Soja’s “Third space” and Edward Casey’s investigations on boundaries and edge conditions, to other sub-theme investigations of concepts of space and form. These concepts of space investigated from different perspectives of Philosophers, Urban theorist, Anthropologist, Geographers, and Architects, are to produce spaces that understand and comment on their context and site. The proposed building is derived from an analysis and processing of the site’s complexities, addressing overlapping and distinguishable layers within the geographical site and social practice. The investigation herein carried out in the context of Maseru, Lesotho, is to address a need identified through youth development agendas and proposes to introduce an Urban Arts Academy in the middle of the city. The proposed building is generated from an understanding and analysis of “Inclusive space” and opens an architectural inquiry to a phenomenological approach of placemaking. The architectural aim is to investigate a design that is for an existing transient music subculture which informs the program and the site to create a space of dialogue between different social and cultural layers. Space is a dynamic construct of forming place within time, in between the dynamism, there is a medium for promoting cohesion instead of separation. A place for inclusive contribution. This approach leads to the research that space is therefore a constantly changing and dynamic substance that is as relative to “a point” as time. In its post-modernist definition, space is not static and just for function, but ever-changing beyond the usual perception of static tangible objects, but also as a construction of identity and culture it remains relative to dialogue
Sampling and extraction methods for soil inorganic N determination to calibrate the EM38 in irrigated fields
No full textPrecise management of N variability in crop fields are required to increase yields and ensure sustainable and economic crop production, whilst not having a negative impact on the environment. A popular type of sensor for characterizing soil variability is the EM38-MK2 that measures apparent electrical conductivity (ECa), operating on the principle of electromagnetic induction (EMI). After analysis, inorganic N results can be calibrated to ECa measurements. It has been established that NH4+-N and NO3ˉ-N can be predicted from ECa.
This study presented three main research aims to: i) compare single and composite samples for the determination of NH4ˉ-N, NO3ˉ-N, and total inorganic N (TIN), ii) determine if the saturated paste extract (SATe) could replace the standard 2.0 M KCl extraction for determination of NH4ˉ-N and NO3ˉ-N, and iii) determine what combination of single or composite ECa measurements and inorganic N at different sampling depths would produce the most statistically significant inorganic N prediction model.
EMI surveys were conducted on four study sites under centre pivots, located on commercial irrigation farms in the districts of Douglas, Luckhoff, Hofmeyr and Empangeni. Using ECa data with the “Electrical Conductivity Sampling Assessment and Prediction” (ESAP) software and it‟s featured “Response Surface Sampling Design” (RSSD) sampling methodology, soil sampling points were identified based on the degree of ECa variability. Before sample collection, additional ECa readings were taken at each sampling point, one in the centre and one on each corner of a 1 m2 area. Afterwards soil samples were collected in the same manner in 300 mm depth increments up to 1500 mm. Samples collected in the centre were considered single, while those from the corners were composited. Concentrations of NH4+-N and NO3ˉ-N in KCl and SATe soil extracts were simultaneously determined colorimetrically.
For the first aim, inorganic N concentrations in KCl extracts was loge transformed and pooled to compare sampling methods irrespective of study site, sampling point, and depth. For the second aim, data of inorganic N concentrations determined in KCl and SATe extracts were transformed and pooled for comparison, irrespective of site, sampling point, sampling method, and depth. The third aim was divided into three parts, determining agreement between single and composite ECa measurements, determining what inorganic N values to use, i.e. what sampling method and extract, and finally model calibration.
Statistical analysis focused on assessing agreement using the Bland-Altman method for assessing agreement on a 95% confidence interval and multiple-linear regression calibration models were developed in Microsoft Excel.
Results revealed poor agreement between single and composite samples for NO3ˉ-N and TIN. A composite sample taken in a 1 m2 area was more suitable when investigating NO3ˉ-N or TIN. Good agreement was found for NH4ˉ-N and a single sample proved sufficient. Agreement between the two extracts was poor for both NH4+-N and NO3ˉ-N and it was concluded that SATe cannot replace KCl for inorganic N determination. Agreement between single and composite ECa measurements was good and one ECa measurement was sufficient per 1 m2 sampling location.
Based on the conclusions from the previous research questions, inorganic N results used for model development were those from composite samples extracted using KCl and an average between the single and composite ECa measurements was used.
Values of inorganic N, ECa and elevation were loge transformed. Results showed that the majority of the calibration models were statistically insignificant except for one sampling depth (900 to 1200 mm) at Douglas (ECa 0 to 750 mm; R2=0.54 and ECa 0 to 1500 mm; R2=0.57). It was concluded that for the sites investigated, inorganic N was not the dominant soil property influencing ECa.SENWES LTDUniversity of the Free Stat
A comparative analysis of the treatment of biodiversity impacts in mining Environmental Impact Assessments (EIAs) before and after 2013: experiences from the Mpumalanga province, South Africa
No full textEnvironmental Impact Assessment (EIA) is one of the environmental management tools employed by the relevant authorities to achieve the principles of sustainable development. Biodiversity Impact Assessment (BIA) studies are undertaken as part of the EIA process to ensure that the proposed development considers the potential impacts on the biodiversity. Studies on the state of South Africa’s biodiversity have revealed that biodiversity and ecosystems in the country are under serious threat; and mining is one of the major threats to the biodiversity. In 2013, the Mining and Biodiversity Guideline (DEA et al., 2013) was published, with the aim of improving the integration of biodiversity into the mining industry. This research analyses the treatment of biodiversity impacts in mining EIAs before and after the publication of this guideline.
In order to achieve the aim of this research, a customised mining BIA report-review package was developed; and it was employed to review 46 mining BIA reports produced before and after 2013. Secondary data – by means of questionnaires were also employed to get an in-depth understanding of the treatment of biodiversity impacts in mining EIAs. The results of the study revealed that most BIAs failed to consider biodiversity issues properly in their assessments. For instance, the BIAs conducted before, and after 2013 received an overall satisfactory score of 43% and 57%, respectively.
Areas of weakness include project description, sensitivity mapping, stakeholder consultation, consideration of alternatives, as well as monitoring. Faithful representation of the biodiversity specialist input to the main mining EIA report showed an improvement after 2013, by receiving an overall satisfactory score of 78%, compared to the 52% received before 2013.
The results also revealed that the majority of the BIA reports complied with the minimum requirements for specialist studies stipulated by the National Environmental Management Act (Act No.107 0f 1998). The analysis of the questionnaires revealed several inadequacies and areas of weakness regarding the treatment of biodiversity impacts. These include poor consideration of indirect and cumulative impacts, failure to incorporate environmental thresholds, and the ecosystem approach – when assessing biodiversity impacts.
A series of recommendations for improving the treatment of biodiversity impacts in mining EIAs was subsequently formulated. The development and implementation of sensitivity mapping guidelines, capacity building for biodiversity specialists and Environmental Assessment Practitioners (EAPs), and the application of the mitigation hierarchy, among others, is proposed to improve the consideration of biodiversity impacts in mining EIAs.UFS Research Masters and Doctoral Bursar
Supporting east Asian students enrolled at a South African university
No full textOver the previous 30 years, most East Asian (South Korea, China, Japan) countries have achieved remarkable economic success, and are entering the global economic market. Therefore, more and more East Asian parents support their children to study in other countries. Chinese parents, for example, may consider that studying overseas inter alia would enhance their children's competitiveness in terms of learning other languages, especially English and understand different cultures, getting a good quality of education, learning from other countries’ different sets of values. They thus consider studying overseas as a long-term investment towards global citizenship.
Due to different language, culture, and learning styles between the East Asian and English-speaking countries, these students often find it difficult to adapt to the new environment. As an East Asian student myself, I had found it difficult to adapt to the circumstances in South Africa. As I could find no reference in literature to the problem in the context of South Africa, the aim of my dissertation was to explore and describe the challenges of East Asian students studying at one South African English-medium university towards improving the support provided by higher education institutions.
Based on my literature review I gathered that East Asian students studying abroad often find challenges with academic and social practices. The literature also highlighted difficulties in terms of transport and accommodation. The level of support varies at different institutions, and in different parts of the world.
Based on my literature review, I developed some interview questions which I posed to six East Asian participants and seven staff members at the University of the Free State. I transcribed the data, and sorted similar themes based on what the literature and data indicated as relevant.
My study showed that East Asian students experience barriers with regard to language and the academic practices. In terms of language, the students shared that it was difficult to understand English, and in particular also to follow the different accents. Adjusting to continuous assessments, with diverse assessment tasks was also difficult, as it is quite different from the systems used in their own countries.The interviews with the staff members revealed that many units exist to assist the students, albeit not specifically for East Asian students. Services include support for international students in terms of administrative issues such as study permits, registration and so forth. There are units that assist students with academic writing, studying methods and many more. For me, the most significant observation was that while the East Asian students were struggling, the university seemed to have numerous support structures in place that could help them to overcome these challenges. However, the students seemed to be unaware of the services that they could make use of. It became clear that it is vitally important that universities find a way to continuously make English as a Foreign Language (EFL) students aware of the services that could assist them
The fluidity of the in-between: a water only fasting center
No full textThis design dissertation investigates the proposal of a Water Only Fasting Centre, 7 Dams, Bloemfontein. The project aims to become the third fasting center in South Africa, and the second owned by Dr Karalis. My interest in water only fasting stems from an interest in natural remedies and homoeopathy. A string of poor health lead to the discovery of the wonders of nature and its ability to heal, without nasty side effects. This being said, western medicine is imperative, and the gap between the two medical fields became apparent. The study thus aims to use the in-between, the gap, or the liminal, as an architectural space of healing and knowledge. The paper is divided into 6 main parts. The fist situates the project and its rationale, using a explorative touchstone as a tool in which a lens can be produced to focus the investigation. Part two highlights challenges and aims of the dissertation and the third explores and grounds the proposal through research and investigations into the typology, topology and morphology. The next section involves a technical report in which the design is quantified, in terms of type, form and site. The fifth synthesises the findings throughout the paper into a design and technical solution. The final part is a reflection of the successes and shortcomings of the project
Indecisiveness on risk preference and time preference choices. Does financial literacy matter?
No full textThe aim of this study is to investigate the relationship between financial
literacy and decisiveness in making risk preference and time preference choices by
university students. The study collected data using a questionnaire, implemented
a multiple price list risk preference and time preference experiment, and administered a financial literacy test on 192 university students (female = 53%).
A maximum of 7 680 risk preference and 7 680 time preference choices were
elicited from the university students. An ordinary least squares regression model
shows that multiple switching or indecisiveness on risk preference and time preference choices increase as financial literacy decreases. University students with
low financial literacy are more likely to switch back-forth between binary lotteries.
Low financial literacy increases behavioural biases and short cuts in making preference choices. Being financial literate helps university students to be decisive in making risk and time preference choices.Publisher's versio