Pub Date : 2024-01-30DOI: 10.17159/sajs.2024/15898
Heidi Prozesky, François B. Van Schalkwyk
The need for evidence on postdoctoral research fellows, or ‘postdocs’, has become increasingly evident globally, as many countries, including South Africa, lack information on these researchers. We used existing sources of quantitative data to provide a longitudinal profile of postdocs at South African public universities. These sources include national research-and-development surveys and data from the national Higher Education Management Information System. Our focus was on postdocs’ representation and research intensity (i.e. time spent on research) within the national research system, as well as on two key demographic features, namely nationality and gender. We draw comparisons with findings reported for other countries to situate our results within the global science system. Interpretation of our results leads us to comment on global and national developments and policies relevant to postdocs.
{"title":"The profile of postdoctoral research fellows in South Africa: Trends over the past two decades","authors":"Heidi Prozesky, François B. Van Schalkwyk","doi":"10.17159/sajs.2024/15898","DOIUrl":"https://doi.org/10.17159/sajs.2024/15898","url":null,"abstract":"The need for evidence on postdoctoral research fellows, or ‘postdocs’, has become increasingly evident globally, as many countries, including South Africa, lack information on these researchers. We used existing sources of quantitative data to provide a longitudinal profile of postdocs at South African public universities. These sources include national research-and-development surveys and data from the national Higher Education Management Information System. Our focus was on postdocs’ representation and research intensity (i.e. time spent on research) within the national research system, as well as on two key demographic features, namely nationality and gender. We draw comparisons with findings reported for other countries to situate our results within the global science system. Interpretation of our results leads us to comment on global and national developments and policies relevant to postdocs.","PeriodicalId":21928,"journal":{"name":"South African Journal of Science","volume":null,"pages":null},"PeriodicalIF":2.4,"publicationDate":"2024-01-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140480635","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"综合性期刊","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-01-30DOI: 10.17159/sajs.2024/11809
A. Nel, A. Morschhauser, F. Vervelidou, Jürgen Matzka
Earth’s magnetic field is a dynamic, changing phenomenon. The geomagnetic field consists of contributions from several sources, of which the main field originating in Earth’s core makes up the bulk. On regional and local scales at Earth’s surface, the lithospheric field can make a substantial contribution to the overall field and therefore needs to be considered in field models. A locally derived regional core field model, named HMOREG, has been shown to give accurate predictions of the southern African region. In this study, a new regional field model called the South African Regional Core and Crust model (SARCC) is introduced. This is the first time that a local lithospheric model, estimated by employing the revised spherical cap harmonic analysis modelling method, has been combined with the core component of CHAOS-6, a global field model. It is compared here with the existing regional field model as well as with global core field models. The SARCC model shows small-scale variations that are not present in the other three models. Including a lithospheric magnetic field component likely contributed to the better performance of the SARCC model when compared to other global and local field models. The SARCC model showed a 33% reduction in error compared to surface observations obtained from field surveys and INTERMAGNET stations in the Y component, and HMOREG showed a 7% reduction in error compared to the global field models. The new model can easily be updated with global geomagnetic models that incorporate the most recent, state-ofthe- art core and magnetospheric field models.
{"title":"A new high-resolution geomagnetic field model for southern Africa","authors":"A. Nel, A. Morschhauser, F. Vervelidou, Jürgen Matzka","doi":"10.17159/sajs.2024/11809","DOIUrl":"https://doi.org/10.17159/sajs.2024/11809","url":null,"abstract":"Earth’s magnetic field is a dynamic, changing phenomenon. The geomagnetic field consists of contributions from several sources, of which the main field originating in Earth’s core makes up the bulk. On regional and local scales at Earth’s surface, the lithospheric field can make a substantial contribution to the overall field and therefore needs to be considered in field models. A locally derived regional core field model, named HMOREG, has been shown to give accurate predictions of the southern African region. In this study, a new regional field model called the South African Regional Core and Crust model (SARCC) is introduced. This is the first time that a local lithospheric model, estimated by employing the revised spherical cap harmonic analysis modelling method, has been combined with the core component of CHAOS-6, a global field model. It is compared here with the existing regional field model as well as with global core field models. The SARCC model shows small-scale variations that are not present in the other three models. Including a lithospheric magnetic field component likely contributed to the better performance of the SARCC model when compared to other global and local field models. The SARCC model showed a 33% reduction in error compared to surface observations obtained from field surveys and INTERMAGNET stations in the Y component, and HMOREG showed a 7% reduction in error compared to the global field models. The new model can easily be updated with global geomagnetic models that incorporate the most recent, state-ofthe- art core and magnetospheric field models.","PeriodicalId":21928,"journal":{"name":"South African Journal of Science","volume":null,"pages":null},"PeriodicalIF":2.4,"publicationDate":"2024-01-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140480877","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"综合性期刊","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-01-30DOI: 10.17159/sajs.2024/17572
H. Human, Robin Crewe, John Sharp
{"title":"Sue Nicolson (1950–2023): Internationally recognised insect physiologist and dedicated mentor","authors":"H. Human, Robin Crewe, John Sharp","doi":"10.17159/sajs.2024/17572","DOIUrl":"https://doi.org/10.17159/sajs.2024/17572","url":null,"abstract":"","PeriodicalId":21928,"journal":{"name":"South African Journal of Science","volume":null,"pages":null},"PeriodicalIF":2.4,"publicationDate":"2024-01-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140484278","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"综合性期刊","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-01-30DOI: 10.17159/sajs.2024/16548
B. V. van Wilgen
{"title":"New ecological textbook for Angola","authors":"B. V. van Wilgen","doi":"10.17159/sajs.2024/16548","DOIUrl":"https://doi.org/10.17159/sajs.2024/16548","url":null,"abstract":"","PeriodicalId":21928,"journal":{"name":"South African Journal of Science","volume":null,"pages":null},"PeriodicalIF":2.4,"publicationDate":"2024-01-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140481766","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"综合性期刊","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-01-30DOI: 10.17159/sajs.2024/16216
Gabriel S. Konayuma
{"title":"The missing link in modern teaching? A review of Co-Teaching and Co-Research in Contexts of Inequality","authors":"Gabriel S. Konayuma","doi":"10.17159/sajs.2024/16216","DOIUrl":"https://doi.org/10.17159/sajs.2024/16216","url":null,"abstract":"","PeriodicalId":21928,"journal":{"name":"South African Journal of Science","volume":null,"pages":null},"PeriodicalIF":2.4,"publicationDate":"2024-01-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140485431","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"综合性期刊","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-01-30DOI: 10.17159/sajs.2024/15899
D. C. Basson, S. van Vuuren, I. Risenga
There is a global concern that rising atmospheric CO2 concentrations may impact the medicinal or nutritional properties of medicinal plants. Portulacaria afra is a South African medicinal plant that is used by traditional healers to treat various skin conditions. The aim of this study was to determine whether elevated CO2 concentrations would affect the medicinal properties of the leaves of P. afra. This was achieved by comparing the phytochemical presence, antioxidant and antimicrobial activity of the leaves of P. afra which were exposed to ambient (420 ppm) and elevated (600 ppm) CO2 concentrations of plants grown in greenhouse conditions. The results revealed that leaf samples that were exposed to elevated CO2 concentrations exhibited a significant increase in flavonoid presence, compared to the control group. The antioxidant activity of the leaves of P. afra (DPPH activity) remained mostly unchanged in the samples that were exposed to elevated CO2 concentrations. The antimicrobial activity efficacy against Cutibacterium acnes increased with increasing global atmospheric CO2 concentration. These findings suggest that P. afra is a resilient medicinal plant and that its leaves may continue to provide relief against certain ailments, despite rising atmospheric CO2 concentrations.
全球都在关注大气中二氧化碳浓度的上升可能会影响药用植物的药用或营养特性。Portulacaria afra 是南非的一种药用植物，传统医学家用它来治疗各种皮肤病。本研究旨在确定二氧化碳浓度升高是否会影响 P. afra 叶子的药用特性。为此，研究人员比较了暴露在环境（420 ppm）和高浓度（600 ppm）二氧化碳环境中、在温室条件下生长的阿芙拉叶片的植物化学成分含量、抗氧化和抗菌活性。结果显示，与对照组相比，暴露于高浓度二氧化碳环境中的叶片样本中黄酮类化合物的含量显著增加。暴露于高浓度二氧化碳的样本中，P. afra 叶子的抗氧化活性（DPPH 活性）基本保持不变。对痤疮棒状杆菌的抗菌活性随着全球二氧化碳浓度的增加而增加。这些研究结果表明，P. afra 是一种生命力顽强的药用植物，尽管大气中的 CO2 浓度不断升高，但其叶片仍可继续缓解某些疾病。
{"title":"The effect of elevated carbon dioxide on the medicinal properties of Portulacaria afra","authors":"D. C. Basson, S. van Vuuren, I. Risenga","doi":"10.17159/sajs.2024/15899","DOIUrl":"https://doi.org/10.17159/sajs.2024/15899","url":null,"abstract":"There is a global concern that rising atmospheric CO2 concentrations may impact the medicinal or nutritional properties of medicinal plants. Portulacaria afra is a South African medicinal plant that is used by traditional healers to treat various skin conditions. The aim of this study was to determine whether elevated CO2 concentrations would affect the medicinal properties of the leaves of P. afra. This was achieved by comparing the phytochemical presence, antioxidant and antimicrobial activity of the leaves of P. afra which were exposed to ambient (420 ppm) and elevated (600 ppm) CO2 concentrations of plants grown in greenhouse conditions. The results revealed that leaf samples that were exposed to elevated CO2 concentrations exhibited a significant increase in flavonoid presence, compared to the control group. The antioxidant activity of the leaves of P. afra (DPPH activity) remained mostly unchanged in the samples that were exposed to elevated CO2 concentrations. The antimicrobial activity efficacy against Cutibacterium acnes increased with increasing global atmospheric CO2 concentration. These findings suggest that P. afra is a resilient medicinal plant and that its leaves may continue to provide relief against certain ailments, despite rising atmospheric CO2 concentrations.","PeriodicalId":21928,"journal":{"name":"South African Journal of Science","volume":null,"pages":null},"PeriodicalIF":2.4,"publicationDate":"2024-01-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140485884","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"综合性期刊","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-01-30DOI: 10.17159/sajs.2024/16701
Johannes Machinya
{"title":"A comprehensive analysis of populism: In the Name of the People","authors":"Johannes Machinya","doi":"10.17159/sajs.2024/16701","DOIUrl":"https://doi.org/10.17159/sajs.2024/16701","url":null,"abstract":"","PeriodicalId":21928,"journal":{"name":"South African Journal of Science","volume":null,"pages":null},"PeriodicalIF":2.4,"publicationDate":"2024-01-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140484224","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"综合性期刊","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-01-30DOI: 10.17159/sajs.2024/17474
Henno Havenga, Ben Coetzee, R. Burger, S. Piketh
{"title":"Response to Simpson (2024): Standard heat stress indices may not be appropriate for assessing marathons","authors":"Henno Havenga, Ben Coetzee, R. Burger, S. Piketh","doi":"10.17159/sajs.2024/17474","DOIUrl":"https://doi.org/10.17159/sajs.2024/17474","url":null,"abstract":"","PeriodicalId":21928,"journal":{"name":"South African Journal of Science","volume":null,"pages":null},"PeriodicalIF":2.4,"publicationDate":"2024-01-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140485498","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"综合性期刊","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-01-30DOI: 10.17159/sajs.2024/17147
M. Bekker
While cheating is nothing new – academics have long been aware of student essays drafted by ‘essay mills’, computer code written by friends or copied from online repositories, or even a human double sitting for an exam on behalf of a less-prepared student – LLMs present the academe with a new level of concern. That is, from students to scientists, writers are now able to turn to LLMs to author academic work from conceptualisation through research and writing 7 , putting in peril the principle of scientific advancement through human reasoning (or sound thinking as articulated through writing)
{"title":"Large language models and academic writing: Five tiers of engagement","authors":"M. Bekker","doi":"10.17159/sajs.2024/17147","DOIUrl":"https://doi.org/10.17159/sajs.2024/17147","url":null,"abstract":"While cheating is nothing new – academics have long been aware of student essays drafted by ‘essay mills’, computer code written by friends or copied from online repositories, or even a human double sitting for an exam on behalf of a less-prepared student – LLMs present the academe with a new level of concern. That is, from students to scientists, writers are now able to turn to LLMs to author academic work from conceptualisation through research and writing 7 , putting in peril the principle of scientific advancement through human reasoning (or sound thinking as articulated through writing)","PeriodicalId":21928,"journal":{"name":"South African Journal of Science","volume":null,"pages":null},"PeriodicalIF":2.4,"publicationDate":"2024-01-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140480233","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"综合性期刊","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-01-30DOI: 10.17159/sajs.2024/13225
J. Bantjes, Sophia du Plessis, Ada Jansen, Philip Slabbert
In Africa, 40% of traffic fatalities are pedestrians – the highest proportion globally. Yet little is known about driver characteristics that are associated with unsafe driving in African countries. We aimed to explore associations between driving practices that endanger pedestrian safety and motorists’ attitudes to the law (i.e. lawlessness and normlessness), controlling for sociodemographic and personality factors. We used the Response Time Method, based on Russell Fazio’s attitude paradigm, to collect information about driver behaviours, attitudes, and personality traits among a sample of 440 motorists. Male gender was associated with unsafe driving, even when controlling for the effects of personality and attitudes to the law. Unsafe driving was also associated with four dimensions of motorists’ personality, namely aggression, impulsivity, risk tolerance, and altruism, even when controlling for sociodemographic factors. Lawlessness (defined as a general disregard for the law) is also an important determinant of unsafe driving, even when controlling for sociodemographic and personality factors. These findings suggest that efforts to improve pedestrian safety in South Africa should focus on changing motorists’ attitudes to the law.
在非洲，40% 的交通事故死亡者是行人，这一比例在全球最高。然而，人们对非洲国家与不安全驾驶相关的驾驶员特征知之甚少。我们旨在探讨危及行人安全的驾驶行为与驾驶者对法律的态度（即无法无天和不守规矩）之间的关联，同时控制社会人口和个性因素。我们根据 Russell Fazio 的态度范式，采用响应时间法收集了 440 名驾驶者的驾驶行为、态度和个性特征信息。即使控制了性格和对法律态度的影响，男性性别也与不安全驾驶有关。即使控制了社会人口因素，不安全驾驶也与驾驶者的四个性格维度有关，即攻击性、冲动性、风险容忍度和利他主义。无法无天（定义为对法律的普遍漠视）也是不安全驾驶的一个重要决定因素，即使在控制了社会人口学和人格因素的情况下也是如此。这些研究结果表明，改善南非行人安全的工作应侧重于改变驾车者对法律的态度。
{"title":"Pedestrian safety: Motorists’ attitudes to the law and driving practices in South Africa","authors":"J. Bantjes, Sophia du Plessis, Ada Jansen, Philip Slabbert","doi":"10.17159/sajs.2024/13225","DOIUrl":"https://doi.org/10.17159/sajs.2024/13225","url":null,"abstract":"In Africa, 40% of traffic fatalities are pedestrians – the highest proportion globally. Yet little is known about driver characteristics that are associated with unsafe driving in African countries. We aimed to explore associations between driving practices that endanger pedestrian safety and motorists’ attitudes to the law (i.e. lawlessness and normlessness), controlling for sociodemographic and personality factors. We used the Response Time Method, based on Russell Fazio’s attitude paradigm, to collect information about driver behaviours, attitudes, and personality traits among a sample of 440 motorists. Male gender was associated with unsafe driving, even when controlling for the effects of personality and attitudes to the law. Unsafe driving was also associated with four dimensions of motorists’ personality, namely aggression, impulsivity, risk tolerance, and altruism, even when controlling for sociodemographic factors. Lawlessness (defined as a general disregard for the law) is also an important determinant of unsafe driving, even when controlling for sociodemographic and personality factors. These findings suggest that efforts to improve pedestrian safety in South Africa should focus on changing motorists’ attitudes to the law.","PeriodicalId":21928,"journal":{"name":"South African Journal of Science","volume":null,"pages":null},"PeriodicalIF":2.4,"publicationDate":"2024-01-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140484688","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"综合性期刊","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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