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Review of thorium-containing fuels in LWRs
Get PDFa School for Mechanical Engineering, Faculty of Engineering, North-West University, 11 Hoffman Street, Potchefstroom, 2531, South Africa b Unit for Energy and Technology Systems, Faculty of Engineering, North-West University, 11 Hoffman Street, Potchefstroom, 2531, South AfricaStemming from a renewed interest in the suitability of thorium as fertile isotope, this study presents an extensive
survey of some of the recent advances on the use of thorium in light water reactors, with the view of informing
researchers and policy makers. The isotopic properties of fertile and fissile material are discussed, with an
emphasis on the suitability and unique characteristics of thorium. The overview is categorized in terms of fuel
design, moderation, neutronic behaviour, thermal-hydraulics, fuel performance, radiotoxicity and proliferation.
A brief scoping of varying perspectives on the economics of thorium in various fuel designs and applications in
open and closed cycles, long residence fuel and fleet applications is presented. In conclusion, a high-level
explanation of dominating factors, rendering various (often divergent) outcomes, is attempted, based on first
principles
Spatial temporal molecular variability of toxigenic Aspergillus strains in South African Commercial maize destined for human and animal consumption.
No full textDoctor of Philosophy in Biology, North-West University, MafikengClimate change is an ongoing event, and how it will influence the various microbial community is localized and a matter of scientific discourse. In Africa, little research has been carried out to examine the effects future climate change will have on fungi and their mycotoxins. With rising temperatures and sporadic rainfall, it is likely that climate change will impact the occurrence of fungi and mycotoxins in terms of type, distribution and concentration. Numerous studies have predicted that, if nothing has been done, future climate change will certainly increase the risk of pre-harvest aflatoxins and these predictions will vary from one geographical location to another. In the last few decades, global attention has been given to mycotoxin contamination of foods/feeds due to mould infestation. Secondary metabolites produced by some members of the genus Aspergillus negatively affect the health of both humans and animals. Therefore, this study is aimed at evaluating the effects of climate variables on the different Aspergillus species and their toxins present in commercial maize from distinct agro-climatic regions of South Africa using conventional methods. Maize samples from 2017 to 2021 harvest seasons were collected from six distinct agro-climatic regions; Western Free State (WFS), Eastern Free State (EFS), Northern Free State (NFS), Southern Free State (SFS), North West (NW) and Gauteng Province (GP) which present the main maize climatic conditions under which maize is cultivated in South Africa. The occurrence of Aspergillus species in maize samples was significantly influenced by the combined effects of maize variety, agro-climatic region as well as the year in which the maize sample was collected. White maize was more contaminated in the year 2017 (34.38%) than the yellow maize (29.31), while the yellow maize was more contaminated in 2020 (58.33%) than white maize (41.01%). Also, in 2017 in NW and WFS agro-climatic regions, white maize was significantly contaminated by Aspergillus species while a significant relationship was observed between yellow maize and Aspergillus species in 2020 in NW. Less than 30% (28.95%) of the 228 isolates subjected to the aflatoxigenic test was found to possess at least one of the aflatoxin biosynthetic genes. Furthermore, a mean total aflatoxinconcentration value of 64.17 ppb was recorded for SA maize which is above the SA set regulatory limit of 20 ppb. While the NW agro-climatic region recorded the overall highest mean total aflatoxin concentration value of 149.64 ppb, the year 2018 saw the highest mean total aflatoxin concentration value of 133.02 ppb. In all, the year 2020 recorded the highest contamination of maize by Aspergillus species (42.4%), this same year (2020) recorded the highest rate of aflatoxin contamination in maize (25.83%). Hence, it is safe to say there is a direct correlation between fungal contamination and mycotoxin production in maize
Relationships between moderate vigorous physical activity, motor- and health-related fitness and motor skills in children
Get PDFJournal Article, Faculty of Health Sciences, Physical Activity Sport and Recreation (PhASRec)-- Potchefstroom CampusBackground: Childhood is an important transitional period for the development of healthy physical activity (PA) behaviours, so it is important to understand its impact on a healthy lifestyle.
Aim: This study aimed to determine the influences of sex, socioeconomic status (SES) and body composition (BC) on the relationships between PA, motor skills, motor- and health-related physical fitness in 5-8-year-olds.
Setting: Participants were a subsample consisting of 299 children (150 boys, 149 girls, mean age 6.83 ± 0.96 years) from the Exercise, Arterial Modulation and Nutrition in Youth South Africa study (ExAMIN Youth SA).
Methods: Anthropometric measures, health-related physical fitness (HRPF), motor-related physical fitness (MRPF), objectively measured PA and demographic information were determined.
Results: Only 66% achieved the recommended 60 min of daily moderate vigorous physical activity (MVPA) with 19% classified as having unhealthy body composition (11% overweight, 8% obese). Fat-free mass and SES revealed small-to-moderate influences on the relationship between MVPA, standing broad jump (SBJ; r = 0.32), predicted VO2max (r = 0.28) and beep levels (r = 0.22). For MRPF, the quality of running (r = 0.12) and balancing were associated with MVPA. Adjusting for sex, BC and SES in the relationship between PA with HRPF and MRPF, reductions in most correlations were observed.
Conclusion: Moderate vigorous physical activity levels were positively associated with HRPF, MRPF and some motor skills in 5-8-year-olds. Socioeconomic status (lower parental income, employment and education negatively influenced the association between MVPA and fitness [beeps, SBJ, O2max]).Contribution: This study provides knowledge with regard to the use of accelerometer for baseline data for PA, MRPF, HRPF as well as motor skills in South African children.Acknowledgements
The authors would like to thank all the parents and children who participated in the study and for the cooperation of the school principals and their staff. Furthermore, the research team members from BC–IT and ExAMIN Youth studies are greatly acknowledged for their dedication and hard work in the project.
Funding information The financial support for the BC-IT study under TC project SAF6020 was received from International Atomic Energy Agency (IAEA), the South African Medical Research Council (SAMRC) and the National Research Foundation (NRF)
A Balancing Act: South African Geography teachers’ Implementation of Teacher-Centered and Learner-Centered Instructional Strategies in Their Classrooms
Get PDFJournal Article. Faculty of Education, North-West University, Potchefstroom CampusLearner-centered instruction fosters 21st-century skills and must be implemented in geography classrooms. In this South African case study, most teachers predominantly implemented teacher-centered instruction. The analysis of the results established a moderate but highly significant relationship between geography teachers’ years of teaching and their implementation of teacher-centered instruction and a weak significant relation in the implementation of individual instructional strategies. Teachers
with more years of teaching implemented more teacher-centered and individual learner-centered instructional strategies than early-career teachers. Teachers stated that learners and parents expected them to teach and that large classes hindered the implementation of learner-centered instruction
Exploring disaster preparedness in an obstetric unit in a district hospital in the Western Cape Province
Get PDFArticle, Faculty of Health Sciences (Quality In Nursing and Midwifery (NuMiQ)--Northwes University, Potchefstroom CampusBackground Research on disaster preparedness in public hospitals is limited, and specialised units such as obstetric departments need to be even more prepared when rendering health care to vulnerable populations. Disasters can be natural, such as floods due to human interventions, sinkholes due to mining, or pandemic occurrences, such as the recent COVID-19 pandemic. Research on disaster preparedness is limited, and even more so in specialised units such as obstetrics and evacuating a ward of maternal and neonatal patients present unique challenges. Being prepared for any disaster is the only assurance of effective patient healthcare during a disaster. This study explored and described
nurses’ knowledge and attitudes regarding preparedness for a disaster in an obstetric unit in a public institution. The study aimed to make recommendations to improve disaster preparedness in an obstetric ward based on the nurses’
knowledge and attitudes.
Methods This study utilised an exploratory, descriptive qualitative design within a contextual approach. The data were acquired through individual interviews that were done using a semi-structured interview schedule. An observational walkabout was performed with the unit manager to validate interviewee responses. The study employed purposive sampling with a sample size of 17 nurses (N = 32, n = 17) and a response rate of 53%. The interviews were transcribed verbatim, and later, the data underwent analysis using theme analysis and a co-coder.
Results The results indicate that the participants demonstrate an awareness of disaster terminology but need more assertiveness in executing the institutional disaster policy. The results illustrate that more frequent training, disaster rehearsals, and simulations should be implemented to improve disaster readiness. Strategies are recommended to enhance preparedness for a disaster in the obstetric unit.
Conclusion The study findings recommend more education and training opportunities that should be regularly instilled as a practice within the obstetric ward. More disaster drills and simulation exercises should be performed to ensure confidence in disaster preparedness. Obstetric staff of all levels should be involved with policymaking and disaster plan development
What is the fate of the ANC? A Critical Analysis of the Party’s Demise in South Africas 2024 General Elections
Get PDFJournal Article, Faculty of Humanities, Afrocentric Governance of Public Affairs (AGoPA)-- Vanderbijlpark CampusThis article problematises the fate of the African National Congress in South Africa in relation to the country’s 2024 general elections. The authors critically analyse the party’s demise following its dominance in SA politics and its ongoing decline in the last decade. In doing so, the authors consider both the internal and external challenges of the party and unpack whether the decline of the party, which has been in power for almost three decades, is because of favouritism for another political party or a demand for alternative policies. The article is a desktop study that relies entirely on secondary sources. The authors made use of thematic analysis in its broadest form. Among the findings of this article is that the ongoing decline of the ANC should not be regarded as a preference by the electorate for an alternative party and that the decreasing voter turnout and voter apathy must be alarming to the state of voter behaviour in the country entirely. The authors further suggest that opposition parties must prioritise engaging and showcasing themselves as the envisaged alternative that will bring the interest of the people of South Africa to the fore
Effect of fluxing inorganic element-bearing acetate composite on the distribution of pyrolytic products from Highveld partially oxidized fine-coal reject and its beneficiated residue
Get PDFJournal Article.School of Chemical and Mineral Engineering, North-West University, PotchefstroomThe role of mineral-matter in coal significantly influences pyrolysis, yet there is no consensus on the behavior of inherent-minerals and carboxylate salts during coal or fine-coal reject (FCR) pyrolysis. This study investigates the effects of carboxylate salts (Ca(C2H3O2)2, Mg(CH3COO)2⋅4H2O, and Fe(C2H3O2)2 composite (CSC) on FCR, demineralized FCR (FCRD), and demineralized > 1.9 g/cm3 FCR sink fraction (SI1.9D) in a Fischer-assay double retort set-up under the following pyrolysis conditions: 500 ◦C and heating rate of 5 ◦C/min for 3 hours in nitrogen. Analytical techniques identified kaolinite, quartz, dolomite, siderite and calcite, and characterized tar precursors, functional groups, carbon associations, and species evolution in FCR, FCR+CSC, FCRD+CSC, SI1.9D, SI1.9D+CSC and their chars. FCR+CSC exhibited the fastest decomposition rate due to extraneous-minerals and CSC interactions. FCRD+CSC and FCR+CSC achieved the highest carbon conversion, tar yield and gas yield, and the lowest char yield compared to SI1.9D and SI1.9D+CSC. The CSC addition increased the S proportion in FCRD+CSC and SI1.9D+CSC chars due to the H2S in-situ capturing to form nano-sulfides and S-bearing amorphous phases. Also, the SI1.9D+CSC blend released a higher CO2 via inherent nano-carbonates reacted with H3O+ from kaolinite/illite transformation, the HF/HCl aqueous solution and acetate decomposition. Tar yield,
polycyclic aromatics, alkylated phenolics, and naphthalene compounds decreased due to hydrogen transfer by CSC, inhibiting secondary cracking of intermediate vapors. These results highlight the catalytic potential of carboxylate salts, dependent on inherent-minerals and dominating maceral groups during coal pyrolysis
Phenotyping Kidney Function in Young Adults With High Blood Pressure: The African-PREDICT Study
Get PDFJournal Article, Hypertension in Africa Research Team (HART), North-West University, Potchefstroom CampusBiomarkers of kidney function, including glomerular, tubular, and fibrotic markers, have been associated with blood pressure in elderly populations and individuals with kidney and cardiovascular diseases. However, limited information is available in young adults. In this study, we compared levels of several kidney function biomarkers between normotensive and hypertensive young adults and explored the associations of these biomarkers with blood pressure within these groups. In this cross-sectional assessment, twenty-four-hour (24-h) blood pressure measurements of 1055 participants (mean age = 24.6 years) were used to classify hypertension as per the 2018 ESC/ESH guidelines. Biomarkers of kidney function included estimated glomerular filtration rate, urinary albumin, alpha-1 microglobulin (uA1M), neutrophil gelatinase-associated lipocalin (uNGAL), uromodulin (uUMOD), and the CKD273 classifier. All urinary biomarkers, except for the CKD273 classifier, were standardized for urinary creatinine (Cr). In the hypertensive group (61.0% White; 73.2% men), urinary albumin-to-creatinine ratio (uACR), uNGAL/Cr and uUMOD/Cr were lower than the normotensive group. In multiple regression analyses, 24-h systolic blood pressure (SBP) (β = 0.14; p = 0.042), 24-h diastolic blood pressure (DBP) (β = 0.14; p = 0.040), and 24-h mean arterial pressure (MAP) (β = 0.16; p = 0.020) associated positively with uA1M/Cr in the hypertensive group, while 24-h MAP positively associated with uACR (β = 0.17; p = 0.017). In exploratory factor analysis, positive associations of 24-h DBP and 24-h MAP with a factor pattern including tubular biomarkers were observed in the hypertensive group (24-h DBP: β = 0.18; p = 0.026, 24-h MAP: β = 0.17; p = 0.032). In the setting of hypertension, high perfusion pressure in the kidneys may play a role in the development of proximal tubule damage and promote early deterioration in kidney function in young adults.he research funded in this manuscript is part of an ongoing research project financially supported by the South African Medical Research Council (SAMRC) with funds from National Treasury under its Economic Competitiveness and Support Package; the South African Research Chairs Initiative (SARChI) of the Department of Science and Technology and National Research Foundation (NRF) of South Africa (GUN 86895); SAMRC with funds received from the South African National Department of Health, GlaxoSmithKline R&D (Africa Non-Communicable Disease Open Lab grant), the UK Medical Research Council and with funds from the UK Government's Newton Fund; as well as corporate social investment grants from Pfizer (South Africa), Boehringer-Ingelheim (South Africa), Novartis (South Africa), the Mediclinic Hospital Group (South Africa) and in kind contributions of Roche Diagnostics (South Africa)
Climate-smart agricultural practices, productivity, and food-nutrition security in rural South Africa: A dataset of smallholder maize farmers
Get PDFJournal Article, Faculty of Natural and Agricultural Science (Agricultural Economics and Extension) -- North-West University, Mahikeng CampusThe intensifying impacts of climate change have adversely affected smallholder maize farmers, leading to low productivity, decreased incomes, and food-nutrition insecurity. As a result, an understanding of farmers’ adaptation techniques to offset the negative impacts of climate change is imperative. Here we present the data on the impact of climate- smart agricultural (CSA) practices on productivity and foodnutrition security (FNS) in the 2022-2023 agricultural pro- duction season among smallholder maize farmers in North- West Province, South Africa. The survey that gave this dataset was conducted via a multistage sampling technique through a well-structured questionnaire from 316 smallholder maize farmers selected from 20 randomly sampled villages in South Africa. The finding revealed that climate change is evident in the study location by the significant decline in productivity and FNS of the smallholder maize farmers. Notably, the productivity of CSA adopters and non-adopters is 13.85 and 7.26,respectively. We estimated the HFIAS of CSA adopters and non-adopters to be 2.23 and 5.85, respectively. Consequently, various CSAs adopted in the study area include drought- tolerant maize varieties (DTMV), mulching, cover cropping, and zero tillage. The study outcomes indicate that to achieve the FAO’s sustainable agricultural goals and create a world free of hunger by 2030, South Africa’s farmers must foster their CSA adoption intensity in order to enhance productivity and FNS through building resilience to climate change
The impact of telecommunications development on the Trade-GDP nexus in South Africa: Application of the ARDL methodology
Get PDFJournal Article, Faculty of Economic and Management Science -- North-West University, Mahikeng CampusThis study investigated the relationship between telecommunications development, trade openness and economic growth in South Africa. It determined explicitly if telecommunications development and trade openness directly impact economic growth or whether telecommunications strengthen or weaken the link between trade openness and economic growth using the ARDL bounds test methodology. The findings reveal that both telecommunications development indicators and trade openness significantly and positively impact South Africa’s GDP in the short and long terms. The study also found that control variables like internet usage and gross fixed capital formation significantly and positively influence GDP. Conversely, inflation was found to consistently affect GDP negatively and significantly. The findings from the ARDL cointegration analysis affirm a long-run economic relationship between the independent variables and GDP. The study also established that telecommunications development slightly distorts trade in the foreign trade-GDP nexus in South Africa. Despite this, the negative interaction effect is not substantial enough to overshadow the positive impact of trade openness on economic growth. From a policy perspective, the study recommends that South African policymakers prioritise enhancing localgoods’ competitiveness in global markets and reducing trade barriers. It also advocates for improving the accessibility and affordability of telecommunications technologies to foster economic development