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The determination of pyrolytic synergies between sewage sludge and low-rank coal
No full textJournal Article, Faculty of Engineering, North--West University-PotchefstroomIn this study, South African sewage sludge (SASS) and turnout North American lignite (NAL) were subjected to analytical pyrolysis and evaluation of synergistic interaction. Mineralogical and chemical properties of the SASS, NAL, SASS and NAL blends and their ashes differed significantly owing to the origin of the samples evaluated . Fourier-transform infrared spectroscopy results showed that both samples comprised of similar functional groups with different transmittance intensities. NAL projected a high hydroxyl intensity at 3500–2800 cm− 1 , corresponding to its higher moisture content and the OH– from kaolinite. The organic matrices of both SASS and NAL consisted mainly of long length-chain fatty acids and long-oil range hydrocarbons (C > 15), but NAL reported a slightly higher elution time owing to signatures of a number of complex aromatic compounds and substitutions such as phenol, naphthalene, glycol and plasticiser (phthalate) compounds. The thermogravimetric analysis indicated that NAL thermal degradation took place over a wider temperature range starting from 350 to 700 ◦C, while SASS thermal-degradation occurred between 250 and 500 ◦C. Also, a slower NAL decomposition rate related to the higher concentration of long-chain hydrocarbons and formation of aromatic clusters via secondary repolymerization reaction as indicated by NMR. The slow decomposition rate and repolymerization reaction contributed to higher activation energy(Ea) requirements for NAL pyrolysis. Interactive blend ratios for the thermal degradation were found to be 80 %SASS:20 %NAL and 20 %SASS:80 %NAL with Ea of 285.24 and 415.72 kJ/mol, respectively. Results obtained from this work provide a starting point towards co-pyrolysis of digested SASS with South African fine coal rejects. Utilization of sewage sludge and fine coal wastes in the thermochemical processes could have potential for fuel production as well as resolving environmental and Human health problems associated with high-cost waste disposal methods
Possible Changes and Trends in Non-COVID-19 Vaccine Prescribing Patterns before and during COVID-19 Pandemic
Get PDFThe Faculty of Health Sciences, School of Pharmacy, North-West University, Potchefstroom 2531, South AfricaDue to the COVID-19 pandemic, many children missed their routine vaccinations globally. There is insufficient evidence on the trends in vaccination coverage in the private healthcare
sector in South Africa. This study explored the changes in childhood vaccination patterns (nonCOVID vaccines) in the private healthcare sector in South Africa using medicine claim data. Using
the information on medication claims from a South African pharmaceutical benefit management
(PBM) company, we performed a quantitative cross-sectional analysis comparing the period before
(2018–2019) and during the COVID-19 pandemic (2020–2021). All patients who made claims within
the study period were included. This study included 67,830 children aged two years and younger. In
particular, from 2018 to 2021, boys (52%) outnumbered girls (48%). Pharmacists consistently held
the predominant prescriber role before and during the COVID-19 pandemic. The proportion of
children receiving non-COVID-19 vaccines was higher before the pandemic (60%) than during the
pandemic (55%). Furthermore, there was a notable decline of 5% in measles vaccination rates during
the children’s first year of life, while a notable increase was observed for measles (5%), hepatitis A
(7.7%), and the pentavalent vaccine (5%) during the second year of life. Governments and private
healthcare providers must take action to enhance vaccination coverage rates for children in their
first year of life to prevent a resurgence of vaccine-preventable diseases. The results obtained in this
study underscore the significance of implementing vaccine catch-up campaigns to address missed
vaccination opportunities arising from the impact of the COVID-19 pandemic. Moreover, pharmacists
emerged as the predominant healthcare providers responsible for administering vaccinations within
the private healthcare sector in South Africa, both prior and during the COVID-19 pandemic. Their
pivotal role in the vaccination process warrants due recognition and should not be underestimated
DEVELOPING MACHINE LEARNING-BASED MODELS FOR OPTIMAL MAINTENANCE SCHEDULING WITHIN THE FOOD INDUSTRY
Get PDFConference Contribution, Faculty of Engineering, North--West UniversityIn the context of the food industry, precisely the company used as a case study, unplanned machine downtimes are mainly caused by ineffective maintenance scheduling that impacts organisational profit. To address this challenge, the study explores predictive maintenance within the food industry and its application to reduce machine inefficiencies and improve
overall decision-making. First, a theoretical background on predictive maintenance and machine learning is provided, followed by the development of the random forest and decision tree models. Company data is pre-processed, and the models are trained and tested using scientific methods from academic literature, including cross-validation and hyperparameter
tuning. One-year future predictions are made for three retail line machines, aiding in proactive maintenance decision-making to reduce unplanned machine downtime. Subsequently, this study contributes towards academia and industry by providing actionable insights for optimising maintenance scheduling and production processes in the food industry
Forming learners through citizenship education to recognise and counter lawlessness in their surroundings
Get PDFDue to various conditions, countries such as Venezuela, Nigeria, and South Africa suffer from
lawlessness (disregard of norms and rules of society) today, threatening their social fabric. It is
contended on the basis of the situation in South Africa that citizenship education1
is arguably a suitable vehicle (in combination with, for instance, religion education, moral education,
and forgiveness education) for offering tolerance, forgiveness, hospitality, and reconciliation
education in schools, all of these as means for counteracting lawless (deviant, errant) behaviour.
Thus far, reflection on citizenship education has, however, been characterised by conceptual
uncertainty, controversy, and a wide range of applications in practice. The paper reports on
theoretical interpretive-constructivist research. This research is aimed at the question of how
citizenship education could be employed to form (equip, educate) young people so that they
can be able to display morally justifiable behaviour and recognise and counteract lawlessness
wherever they encounter it in their lifeworld
Plant-parasitic nematodes associated with bush tea (Athrixia phylicoides) in South Africa and their relationship with physico-chemical soil properties
Get PDFArticle, Faculty of Natural and Agricultural Sciences (Unit for Environmental Sciences and Management)--Northwest University, Potchefstroom CampusBush tea (Athrixia phylicoides) is an aromatic, perennial, leafy shrub that is endemic to the northeastern mountain ranges of South Africa and has a high potential for commercialisation as an alternative to caffeine-containing tea. During the summer and winter of 2018-2019, a survey was carried out at nine localities in the northeastern regions of South Africa to study the diversity of nematodes associated with bush tea and, in terms of frequency of occurrence and abundance, identify the dominant plant-parasitic nematodes. Twenty-one plant-parasitic nematode species belonging to 14 genera were identified in 90 rhizosphere soil and root samples. Meloidogyne and Helicotylenchus were the dominant plant-parasitic nematode genera. Meloidogyne javanica and Scutellonema brachyurus were found at all localities, followed by M. enterolobii, Pratylenchus brachyurus, Rotylenchulus parvus, H. martini and S. truncatum (found at 7-8 localities). Other species identified included Criconema corbetii, C. sphaerocephalus, C. xenoplax, Criconemoides ihlathum, C. parvus, Discocriconemella glabrannulata, H. dihystera, H. erythrinae, H. paraplatyurus, Hemicycliophora typica, M. hapla, M. incognita, Rotylenchulus unisexus and R. clavicaudatus. Individuals of Crossonema, Paratylenchus, Ogma, the Xiphinema americanum-group and X. americanum sensu lato could not be identified to species level due to the low number of specimens present in the samples. Comparison of the two methods used to identify the Meloidogyne populations to species level shows that morphological identification (particularly perineal pattern morphology) provided a more complete picture of the Meloidogyne species present in the samples compared with the molecular SCAR-PCR technique. High levels of Cu, K and pH were associated with the highest relative population densities (RPD% = average population density of a nematode genus/total nematode population density ×100) of Meloidogyne, whilst high levels of Al and soil resistivity were associated with the lowest RPD% of Meloidogyne. By contrast, high levels of K and pH were associated with the lowest RPD% of Helicotylenchus, whilst high levels of Al and soil resistivity were associated with the highest RPD% of Helicotylenchus
The Diffusion Tensor of Protons at 1 au: Comparing Simulation, Observation, and Theory
Get PDFArticle, Faculty of Natural and Agricultural Sciences (Centre for Space Research (CSR)--Northwest University, Potchefstroom CampusThe natural variation in plasma parameters observed at 1 au can lead to a variation in transport parameters, such as diffusion and drift coefficients, for energetic charged particles of solar and galactic origin. Given the importance of these parameters to particle transport studies, this variation is investigated through test particle simulations over a range of energies in the presence of simulated turbulence with properties corresponding to an ensemble of observed turbulence conditions at Earth. The resulting transport coefficients are then compared with observational estimates from the literature, as well as the predictions of several scattering theories. Parallel and perpendicular mean free paths are shown to vary widely, for the former in agreement with prior observational estimates, but not for the latter. Furthermore, a large disparity between the predictions of theory and the simulation results is noted for the perpendicular mean free path. As such, these results indicate that particle transport studies, particularly predictive ones, need to take into account this natural variation in transport coefficients
An exploration of translated collocations in the Constitution of South Africa: a corpus-based study
Get PDFArticle, Faculty of Humanities (SA Centre for Digital Language Resources (SADiLar)--Northwest University, Potchefstroom CampusCollocations, or words that occur in proximity to one another, are a linguistic phenomenon that appears in all human languages. Their translation tends to pose a considerable problem for translators because equivalence in meaning is difficult to achieve. This article explores how the collocations in the English version of the Constitution of South Africa have been translated into three Nguni languages, namely Zulu, Swati and Ndebele. Since these languages are closely related, this investigation demonstrates the degree to which lexical collocations are translated differently and whether the translators used the same strategies. ParaConc is used to extract data from the different versions of the Constitution of South Africa. The analysis is qualitative in nature, using descriptive and comparative approaches. By comparing the different collocations in the translations, we establish the way in which the collocations have been translated and also whether the source text message has been conveyed accuratel
The pragmatic nature of focalisation in John 4:1–42: Reading John as a performative text
Get PDFJournal Article, Faculty of Theology, North--West University-PotchefstroomThis article suggests that the process of crafting a narrative reflects the author’s intentional introduction of bias to guide the reader towards taking specific actions based on their reading. The reader is intentionally steered towards a particular cognitive and pragmatic engagement with the text through the author’s selection, organisation and presentation of narrative materials. This claim forms the impetus for the current exploration. The article explores the pragmatic nature and/or power of the author’s selection of narrative material in John 4:1–42 on the reader. It seeks to demonstrate that the selection and presentation of narrative material are not neutral in their pragmatic intent. While acknowledging a few insightful contributions to this topic, this article contends that certain pragmatic dynamics related to narrative material selection have not been extensively explored by scholars, particularly in the context of utilising focalisation as an analytical tool. Intradisciplinary and/or interdisciplinary: The distinctive contribution of the article lies in its demonstration that focalisation, when employed as an analytical tool, particularly in the context of John 4:1–42, exerts pragmatic effects on the implied reader of the tex
Synthesis and In Vitro Antibacterial Evaluation of Mannich Base Nitrothiazole Derivatives
Get PDFJournal Article, Faculty of Health Science, North-- West University-PotchefstroomNitrothiazole derivatives have been reported to exhibit activity against aerobic, anaerobic, and microaerophilic bacteria. This activity profile makes the nitrothiazole compound class an ideal lead source against Mycobacterium tuberculosis, which flourishes in varied environments with different oxygen concentrations. In this work, we investigated six nitrothiazole derivatives for antitubercular activity. The compounds exhibited potent activity, with compounds 9 and 10 possessing an equipotent MIC90 value of 0.24 μM. The compounds were investigated for cytotoxicity against HEK293 cells and hemolysis against red blood cells, and they demonstrated no cytotoxicity nor hemolytic effects, suggesting they possess inherent antitubercular activit
