Academy of Science of South Africa (ASSAf): Open Journal Systems
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Radiocarbon-dated evidence for Late Pleistocene and Holocene coastal change at Yzerfontein, Western Cape, South Africa
No full textWe report radiocarbon dates obtained from on-shore marine and near-shore terrestrial deposits near Yzerfontein, on the West Coast of South Africa. These deposits include Late Pleistocene shell concretions from the southern end of 16 Mile Beach and a marine shell deposit inland of the coastal Rooipan (Red Pan); mid-Holocene coastal pan deposits exposed by modern storm erosion of the sandy 16 Mile Beach; and four Holocene storm beach deposits on a rocky shore to the south. We interpret the results in terms of local geomorphology constraints on sea-level fluctuations. The eastern margin of Rooipan is a >40 ka elevated beach deposit in a dune cordon that separates it from the adjacent Yzerfonteinpan. Both pans have gypsum deposits up to 2 m thick formed by repeated marine overwash. Saline pan deposits that are exposed intermittently on the beach are mid-Holocene and indicate a former westward extension of Rooipan. This is in contrast to storm beaches dating 8000–2600 cal BP at higher elevations on a rocky platform further south. This suggests that a dune barrier existed seaward of the present shoreline near Rooipan at this time. The coastal changes described here show that deposition and erosion can be affected significantly by the local palaeogeomorphology and cannot be ascribed solely to sea-level change.
Significance:
Mollusc shells from Yzerfontein, Western Cape Province, South Africa, show radiocarbon ages ranging from >40 000 years to a few decades before present. There is evidence for elevated sea levels between 8000 and 2600 years ago, and sea levels similar to the present in the last 2000 years. Neither the elevation of the deposits nor their ages conform to published sea-level change curves for the Western Cape coast. Inundation by rising sea levels in the Holocene was not spatially uniform. Former and present geomorphology have had a significant effect on deposition and preservation of indicators of sea-level change
Corporate tax avoidance: Is South African society negatively affected by chartered accountant CEOs?
No full textCorporate tax avoidance can impede governments’ spending towards social and economic initiatives that can increase infrastructure development, economic growth, and equality, and reduce poverty. Yet, why some companies avoid more tax than others is not adequately understood, and, in particular, research regarding the influence of CEO-characteristics on tax avoidance, is lacking. This study is an empirical investigation into the influence of a CEO’s tax knowledge and tax awareness, construed as a ‘CEO effect’, on corporate tax avoidance, using data from the 112 largest listed companies on the Johannesburg Securities Exchange between 2004 and 2018. We found that the CEO effect, not measured before, does not have an observable influence on the level of corporate tax avoidance. This finding assuages possible concerns that chartered accountants, and particularly chartered accountants in the top leadership positions in large companies, are more shareholder oriented, to the detriment of the interests of society, as suggested in the literature.
Significance:
Our findings suggest less influence of the CEO, as an upper-echelon member, on companies’ behaviour, such as corporate tax avoidance, than other published studies have found. Moreover, the findings indicate that the tax knowledge and awareness construed as a CEO effect, does not influence corporate tax avoidance. In the main, the results provide little support for claims made by the South African Institute of Chartered Accountants, the chartered accountant’s regulatory body, that chartered accountants can help companies to avoid tax to increase profits. This may sway society’s view of the chartered accountant and their role in the South African economy
Decreasing trend in SO2 concentrations over Durban: 2004 - 2014
No full textThe climatology of ambient SO2 air pollution was investigated in Durban, South Africa using data collected by seven air quality monitoring stations (Ferndale, Grosvenor, Jacobs, Wentworth, Settlers School, Southern Works and Prospecton) operated by eThekwini municipality (2004–2014, 2018-2019). These sites constitute a mix of urban and industrial locations. Yearly average trends indicated that no site exceeded the yearly average national guideline (19ppbv) 2004-2014, 2018-2019. Southern Works, Wentworth and Jacobs, recorded highest yearly averages, a consequence of situation within Durban South Industrial Basin (DSIB) while Ferndale recorded lowest yearly averages, a reflection of location in an urban environment. Results of linear fitting to yearly average data (2004-2014) indicated negative trends (all sites). The largest trend was recorded at Jacobs (-0.48ppbv yr-1) and smallest trends observed at Prospecton (-0.12ppbv yr-1), Ferndale (-0.084ppbv yr-1) and Grosvenor (-0.024ppbv yr-1). Using these linear trends, projected SO2 levels were calculated and compared to actual data where it existed (2019 - Wentworth, Settlers, Prospecton), (2018, 2019 Southern Works). Comparison of actual with projected data indicated that except for Prospecton, projected yearly averages are lower than actual yearly averages for these sites. The largest difference between projected and actual data occurred for Southern Works in 2019 (4.10 ppbv). Monthly averages displayed periodic behaviour with maxima recorded in winter and minima in summer. Highest monthly averages were consistently recorded at Wentworth, Jacobs or Southern Works. Maximum monthly average (2004- 2019) was reported at Jacobs, June 2009 (21.71± 2.82ppbv) while minimum monthly average (2004–2019) was reported at Ferndale, December 2012 (0.32±0.04ppbv).
Previous Durban SO2 studies are considerably older or of shorter duration than the analysis presented here and are limited as they principally focus on yearly average trends. The determination of SO2 levels over additional averaging periods (monthly average, seasonal variation, seasonal average) coupled with a larger data set and the comparison across sites (industrial vs urban) provides a more detailed exposure profile as experienced by individuals living and working in the eThekwini municipality and thereby expands on previous investigations
Assessing anthropogenic contribution to PM2.5 from an urban residential area of Lagos, Nigeria using aliphatic hydrocarbon compounds as indicators
No full textAliphatic hydrocarbons in PM2.5 samples from a residential area of Lagos, Nigeria, were quantified using a Curie-point pyrolysis–gas chromatography–mass spectroscopy (CPPGC/MS). The total concentrations of ∑n-alkanes (C20-C34), hopanes (∑4Hopanes), and steranes (∑3Steranes) ranged from 1.8 to 146.6 ng m-3 (avg. 43.6 ± 35.1 ng m-3), 0.0 to 89.9 ng m-3 (avg. 18.7 ± 25.9 ng m-3), and 0.0 to 26.0 ng m-3 (avg. 3.3 ± 6.7 ng m-3), accounting for 0.2%, 0.1%, and 0.01% of the total PM2.5 mass concentrations, respectively. They also accounted for, 1%, 0.4% and 0.1% of the organic matter content, respectively, making them non-negligible component of the organic matter in this region. An evaluation of the n-alkanes source diagnostic indices revealed that engines powered by gasoline and diesel were the main sources of particulate matter aliphatic hydrocarbons in this area of Lagos, consistent with the results obtained from steranes and hopanes profiles. Based on the air mass trajectories, both local and regional air mass transports showed a significant influence on the amounts of carbonaceous materials and aliphatic hydrocarbon compounds arriving at the study site. The results from this study established the occurrence of anthropogenic air pollution in Lagos residential area with a major contribution from petrogenic sources
Professionalism in South African Dental Practice
Full text linkAs we navigate the complex landscape of oral healthcare in South Africa, we find ourselves at a critical juncture where our collective wisdom and ethical commitment are challenged. This editorial is a call to action—a reminder of our paramount responsibility to our patients and to the field of dentistry itself. We must address a pressing issue that has, at times, remained hidden beneath the surface: the dangers of neglect in the treatment of our patients’ dental conditions
The Dental Professionals’ hearing loss and its silent role in affecting our careers and systemic health
Full text linkIn the bustling world of healthcare, dentistry often takes a backseat when it comes to discussions about occupational hazards. While the risks of musculoskeletal problems, exposure to infectious diseases, and stress are frequently acknowledged, there is a silent threat that looms over dental professionals - noise-induced hearing loss (NIHL).This article aims to shed light on the often-overlooked issue of hearing loss in the dental profession, emphasizing its profound impact on both careers and systemic health. Additionally, we will explore preventative measures to mitigate this burgeoning concern
Dear Editor
Full text linkI refer to your editorial in the SADJ April 2022 77(3), and wish to highlight the need of the dental profession to take heed of rising antimicrobial resistance rates, and to focus on modifying their prescribing practices in an effort to mitigate this global crisis.
To understand and contribute to antibiotic stewardship, it is important that dental practitioners, including dental students, have the necessary knowledge of correct antibiotic prescribing guidelines and antimicrobial resistance. The overuse and misuse of antibiotics have contributed to the rise of antimicrobial resistance worldwide, with dentistry playing a part in the rise of antimicrobial resistance globally
Desmoplastic Fibroma: a benign neoplasm mimicking a malignancy
Full text linkA four-year-old African male patient presented to our clinic with a two-month history of a fi rm, warm lesion involving the right side of his face. The lesion presented as a bleeding papillary mass in the 85/46 region that extended to the floor of the mouth, causing displacement of the tongue (Figure 1A-B). Upon cone-beam computed tomography (CBCT) examination, an expansile homogenous intermediate density lesion was noted with complete destruction of the bucco-lingual cortical bone. Discernible extensions were identified in the anteroposterior plane from the region of the 84 to the posterior mandible involving the right corpus, developing 46, angle and ramus but spared the condyle and coronoid processes. The lesion extended inferiorly below the epiglottis and showed a reduction of the hypopharynx. Marked bucco-lingual expansion with soft tissue swelling was noted (Figure 2A-D). An incisional biopsy was performed under general anaesthesia, and histological examination rendered a diagnosis of desmoplastic fi broma (DF)
Complexities of competition regulation in Zimbabwe’s mobile money sector
No full textThis study explores the complexities of competition regulation in Zimbabwe’s mobile money sector—through an analysis of EcoCash’s market position and practices, and the regulatory steps taken in response. The study is grounded in the competition complaint made in 2014 by Zimbabwean banks against EcoCash to the Competition and Tariff Commission (CTC), wherein EcoCash was alleged to have initially refused to share its unstructured supplementary service data (USSD) infrastructure with banks; and then later to have granted access only on discriminatory terms. The research assessed the market structure and market power in the Zimbabwe mobile money sector; the regulatory challenges that these market features pose; the market power and conduct of EcoCash; and the effectiveness of the measures taken by regulators to address the competition concerns raised in relation to EcoCash. The findings indicated that, in spite of regulatory attempts to dilute its power in the market, EcoCash was, at the time of the core data collection in 2021–22, still in a dominant position in Zimbabwe’s mobile money market
Online Platform Privacy Policies: An Exploration of Users’ Perceptions, Attitudes and Behaviours Online
No full textIn January 2021, Meta (then Facebook) published an update to its WhatsApp privacy policy which included, among other things, a decision to share some user data with Facebook. This action, together with previous events like the notorious Cambridge-Analytica data breach, has sparked debates about the protection of online privacy, specifically the balance of rights and responsibilities relevant to the protection of social media user data. This qualitative study contributes to that debate by exploring the perceptions and reactions of South African WhatsApp users to these policy changes. The findings highlight the significance of platforms like WhatsApp in the daily socio-economic activities of users in developing countries. This reliance on social media for communication and access to vital information creates an imbalance of power between users and platform owners. The situationis worsened by the lack of effective regulatory frameworks that governments and institutions in developing countries can use to enforce their privacy laws, leaving users vulnerable to potential exploitation from digital platforms. This study contributes to the broader discourse on safeguarding online privacy as Western technology companies continue to gain access to data that is generated by an ever-increasing global user base