Academy of Science of South Africa (ASSAf): Open Journal Systems
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Comprehensive characterization of selected South African brines
No full textSouth Africa produces significant quantities of brines but there is insufficient information on their biological and physicochemical characteristics and nature, which limits the ability to propose sustainable brine handling procedures. This study aimed to comprehensively characterize selected brines from major brine-producing industries in South Africa. This was achieved through an analysis of the majority of the brine constituents, thereby allowing for the proposal of suitable brine handling procedures, the identification and harnessing of potential economic value, as well as the identification of the environmental impact of the brines. The brines were analysed for physical, metallic, organic, and inorganic constituents using a variety of methods including inductively coupled plasma-mass spectrometry (ICP-MS) and gas chromatography-mass spectrometry (GC-MS). The total dissolved solids (TDS) of most of the brines was below 35 000 mg/L and it was concluded that most South African brines may be brackish. All the brines contained toxic constituents in concentrations that exceeded set discharge and re-use limits. It was concluded that comprehensive characterization is crucial in understanding the quality of brines and is a crucial step in proposing suitable brine handling strategies
Production of subsurface drip-irrigated okra under different lateral spacings and irrigation frequencies
No full textIn this study, an experiment was conducted to investigate the optimum lateral spacing and irrigation frequency for subsurface drip irrigated okra in the semi-arid region of Haryana (India). Two lateral spacings (45 cm and 60 cm) and four irrigation frequencies (daily, after 1, 2 and 3 days) were selected to grow okra in the Kharif season of 2019 and 2020. The effect on soil water dynamics, growth parameters, efficiency and yield were assessed using equal amounts of water under all the treatments on the basis of pan evaporation. The results from the study depict that the overall soil moisture decreased laterally, but increased vertically downward with the increase in the irrigation interval. On the basis of soil water dynamics, plant growth parameters, efficiency and yield of okra, it was concluded that subsurface drip irrigation with daily irrigation at 45 cm lateral spacing gives better performance than all other treatments in sandy loam soil. The present study highlights the significance of proper irrigation frequency and lateral spacing for maximum production of okra. Using these guidelines, the income of okra growers/farmers in the semi-arid region may be increased by choosing the best frequency and lateral spacing of subsurface drip irrigation
MANDATORY COVID-19 VACCINATIONS AT UNIVERSITIES IN SOUTH AFRICA: GUIDANCE FROM THE UNITED STATES AND THE EUROPEAN UNION
No full textDuring the past two decades, immunisation has saved millions of lives and prevented countless illnesses and disabilities in South Africa. Vaccination is the most important thing we can do to protect ourselves and our children against ill health. Vaccinations prevent up to three million deaths worldwide every year. However, the World Health Organization (WHO) has listed vaccine hesitancy as one of the biggest threats to global health. Vaccine hesitancy entails people with access to vaccines delaying or refusing vaccination. In addition to vaccine hesitancy, many people are of the view that it infringes on their fundamental human right to bodily integrity. However, this article presents findings that suggest that this right can be limited because everyone has a fundamental right to be protected from the spread of the disease. Tensions have increased as more vaccine mandates are implemented. Businesses continue to review and revise their Covid-19 vaccination policies as new mutations emerge and employers may be asking what they can do if workers refuse to get the jab. Some employers have dismissed employees or put them on unpaid leave. Others have required unvaccinated employees to submit to weekly testing and take other safety precautions. In terms of the Code of Practice: Managing Exposure to SARS-COV-2 in the Workplace, 2022, the identifiable hazard relating to Covid-19 that workers face is the transmission of virus by an infectious person to others in the workplace. The Regulations for Hazardous Biological Agents, 2022 lists SARS-COV-2 as a hazardous biological agent that places legal responsibilities on employers to mitigate the associated risks. Each situation requires special measures to be implemented by employers in order to prevent the transmission of the virus. Universities in South Africa are also faced with this conundrum regarding the mandating of vaccines. This article examines and discusses mandating vaccines in South Africa, especially at universities, with guidance received from international instruments such as the European Union and countries such as United States. Various legislative and policy frameworks are also analysed
AN EMPLOYER’S ABILITY TO SUBSTITUTE A DISCIPLINARY ENQUIRY SANCTION – PART 1
No full textIt is common practice for employers to appoint an external chairperson to preside over a disciplinary enquiry which has been convened for purposes of investigating allegations of misconduct against an employee. The external chairperson is ordinarily mandated to decide on guilt, and to the extent that there is a guilty finding, to recommend or impose the appropriate disciplinary sanction.Employers often tend to have expectations that the external chairperson will, after having found the employee guilty of the alleged misconduct, impose a sanction of dismissal depending on the gravity of the alleged misconduct . The expected outcome of dismissal, however, does not always occur. An external chairperson may impose a sanction short of dismissal after considering an employee’s mitigating circumstances. An employer’s dissatisfaction with the disciplinary sanction may result in the employer instituting an internal review process to review the external chairperson’s disciplinary sanction, whilst in other cases, employers may resort to unilaterallysubstituting the external chairperson’s disciplinary sanction with a sanction of dismissal. The employer’s disciplinary code and procedure or the collective agreement regulating the disciplinary procedure in the workplace may or may not make provision for the substitution of the disciplinary sanction. In circumstances where there is no provision for the substitution of the disciplinary sanction, the employer’s conduct of substituting the disciplinary sanction raises questions regarding the applicability of the “double jeopardy” principle which means, in an employment context, that an employee should not be subjected to more than one disciplinary enquiry on disciplinary charges arising from the same set of facts.It is, however, a well established principle that employers who are classified as organs of state can review their own decisions. This includes decisions of chairpersons who are appointed to preside over disciplinary enquiries and further decide on the appropriate disciplinary sanction. In the latter case, and in circumstances where the organ of state is dissatisfied with the disciplinary sanction, itmay institute review proceedings in the Labour Court to review and set aside the chairperson’s decision. This recourse is, only available to organs of state and not private sector employers.This article seeks to determine whether it is permissible for an employer to substitute an external chairperson’s disciplinary sanction, and, if so, the circumstances under which an employer is permitted to do so and the procedure which should be followed in such an instance. The article is written in two parts Part 1 covers the employer’s ability to revisit a disciplinary sanction and Part 2 concentrates on the conflicting judgments involving the South African Revenue Services conduct of substituting disciplinary sanctions, alternative avenues to the unilateral substitution of a disciplinary sanction and the conclusion
A Review of the Agroecological Farming System as a Viable Alternative Food Production Approach in South Africa
No full textInput-intensive production systems characterise industrial agriculture as an unsustainable means to address food and nutrition security and sustainable livelihoods. Extensive empirical evidence supports the diversification and reorientation of industrial agriculture and incorporates ecological practices, viewed as essential for achieving balanced and productive farming systems. An agroecological farming system is a viable alternative approach that can improve food production, especially for the most vulnerable communities and households. Furthermore, substantial proof and supporting evidence show that such a system is key to increasing dietary diversity at the local level and reducing the multiple health and environmental risks stemming from industrial agriculture. This paper, therefore, aims to demonstrate the benefits of the agroecology food system through an evidenced-based approach that shows how the broader agricultural network structures can play a meaningful role, particularly for impoverished households in today’s reality. The methodology is centred on a structured literature review that analyses urban agriculture, agroecology and food insecurity. Notably, ground-truthing, practical experiences and field observation of agroecological farming were deployed. This paper emphasises the practical application of the agroecological approach in urban and peri-urban settings. Several evaluation reports on local and provincial initiatives show that very few households engage in food gardens and urban agriculture. These households do not use their backyards or nearby open spaces for several reasons, such as stringent city by-laws, restricted access to land, little or no knowledge of innovative or alternative farming practices, and a general lack of interest. Furthermore, limited resources such as water and energy and lack of capacity building and training implementation are additional constraints hampering small-scale food gardens and farms in other settings. The Agroecology systems approach is viewed as one of the key solutions to tackling these problems
The Complexity of Care and the Dunning-Kruger Effect
Get PDFThere appears to be an increase in litigation against general dental practitioners which is increasingly due to clinicians exceeding their competence, because they may not be aware that they lack the required skills: the so called Dunning-Kruger effect. The purpose of this paper is first, to briefly explain the Dunning-Kruger effect, and second, to propose guidelines for dentists confronted with differing levels of complexity of care, in order to increase practitioners’ awareness of their competence, and by extension, their limitations. An example of complexity levels is given using the discipline of Prosthodontics. It is concluded that there needs to be a revision of the scope of practice for dentistry, which currently provides an “anything goes” approach; a revision of Rule 21 of the Health Professions Council of South Africa, whose provisions need to be more precise as they are currently being ignored; and a revision of the system of providing accreditation for CPD courses and in particular for the presenters and content of those course
Embracing new technology, with caution
Get PDFDental manufacturers frequently present clinicians with new “cutting edge” materials, devices or technology. These usually come with great promise for bettering the status quo in their practices, and of putting them ahead of their colleagues in the market place. However before succumbing to the advertorial hype, and abandoning their old practices, materials or equipment, practitioners need to evaluate the new offering against the “gold standard” if one exists. This entails comparing it to “the benchmark” practice/ product that is routinely used under reasonable conditions, and answering a number of clinically and scientifically pertinent questions. If they are then confident it has beenthrough extensive trials, the results have been analysed with appropriate tests by independent investigators, and the reporting thereof is accurate, reliable, repeatable, sensitive, specific and clinically applicable, they may consider making practice changes. While it is admirable for clinicians to be open minded and willing to embrace and adapt to modern technology, this should only be done if the change has been proven superior to reliable routine practices. It is incumbent on all practitioners to keep abreast of current trends through the many platforms available. They should also strive towards being life-long learners who are curious, open minded, flexible, willing to learn new skills, and open to adapting their work to embrace advances. This will hopefully lead to practitioners having more fruitful careers, and equip them to provide the best possible service and care to their patients
Surveillance of specific pathogens on mobile phones in aerosol and non-aerosol generating dental clinics during the COVID pandemic
Get PDFFollowing COVID-19 protocols implemented globally, it is prudent to extend this to mobile phones, regarded as carriers of microbes, as these are used extensively in clinical settings for learning and patient care. Was to determine types of microbes harbored on mobile phones and related hygiene practices whilst using these in aerosol and non-aerosol generating dental settings. This cross-sectional study was conducted in two parts: A laboratory study to determine the prevalence of microbes on mobile phones and a questionnaire survey to determine the related knowledge and behavior of phone users in both aerosol and non-aerosol generating dental clinics. All proper protocols (consent, ethics) were adhered to. A small percentage (27.2%) of swabs of mobile phones yielded a positive bacterial culture, of these 72% were from the AGP dental setting. Gram positive and negative microorganisms were distinguishable, indicating a diverse group of microbes. Students and staff indicated good mobile phone hygiene practices, but there is place for improvement. Their related knowledge of disinfectants and use were acceptable, but not having mobile phone coverings was problematic. Faculty protocols for disinfecting mobile phones and standardized guidelines for its use in aerosol or non-aerosoclinics is recommended
