Scielo RSS <![CDATA[South African Journal of Science]]> http://www.scielo.org.za/rss.php?pid=0038-235320180006&lang= vol. 114 num. 11-12 lang. <![CDATA[SciELO Logo]]> http://www.scielo.org.za/img/en/fbpelogp.gif http://www.scielo.org.za <![CDATA[<b>Rapid change, no simple solutions</b>]]> http://www.scielo.org.za/scielo.php?script=sci_arttext&pid=S0038-23532018000600001&lng=&nrm=iso&tlng= <![CDATA[<b>Draft White Paper on Science, Technology and Innovation neglects to prioritise issues of performance and human capability</b>]]> http://www.scielo.org.za/scielo.php?script=sci_arttext&pid=S0038-23532018000600002&lng=&nrm=iso&tlng= <![CDATA[<b>On the power of restraint in the writing of lives: Humanities Book Award 2018</b>]]> http://www.scielo.org.za/scielo.php?script=sci_arttext&pid=S0038-23532018000600003&lng=&nrm=iso&tlng= <![CDATA[<b>ASSAf consensus study on the ethical, legal and social implications of genetics and genomics in South Africa</b>]]> http://www.scielo.org.za/scielo.php?script=sci_arttext&pid=S0038-23532018000600004&lng=&nrm=iso&tlng= <![CDATA[<b>Professor ADM (David) Walker: World-class physicist (1937-2018)</b>]]> http://www.scielo.org.za/scielo.php?script=sci_arttext&pid=S0038-23532018000600005&lng=&nrm=iso&tlng= <![CDATA[<b>A holistic story of South African cricket across time, space, identity, race and gender</b>]]> http://www.scielo.org.za/scielo.php?script=sci_arttext&pid=S0038-23532018000600006&lng=&nrm=iso&tlng= <![CDATA[<b>Reducing inequality and carbon emissions: Innovation of developmental pathways</b>]]> http://www.scielo.org.za/scielo.php?script=sci_arttext&pid=S0038-23532018000600007&lng=&nrm=iso&tlng= Professor Harald Winkler is the recipient of the 2017/2018 NSTF-South32 Special Annual Theme Award: Sustainable Energy for All (in recognition of the United Nations 'International Decade of Sustainable Energy for All'). <![CDATA[<b>Alpha and sigma taxonomy of <i>Pan</i> (chimpanzees) and Plio-Pleistocene hominin species</b>]]> http://www.scielo.org.za/scielo.php?script=sci_arttext&pid=S0038-23532018000600008&lng=&nrm=iso&tlng= Professor Harald Winkler is the recipient of the 2017/2018 NSTF-South32 Special Annual Theme Award: Sustainable Energy for All (in recognition of the United Nations 'International Decade of Sustainable Energy for All'). <![CDATA[<b>Are managed pollinators ultimately linked to the pollination ecosystem service paradigm?</b>]]> http://www.scielo.org.za/scielo.php?script=sci_arttext&pid=S0038-23532018000600009&lng=&nrm=iso&tlng= Professor Harald Winkler is the recipient of the 2017/2018 NSTF-South32 Special Annual Theme Award: Sustainable Energy for All (in recognition of the United Nations 'International Decade of Sustainable Energy for All'). <![CDATA[<b>Research biobanks: A two-faced future</b>]]> http://www.scielo.org.za/scielo.php?script=sci_arttext&pid=S0038-23532018000600010&lng=&nrm=iso&tlng= Professor Harald Winkler is the recipient of the 2017/2018 NSTF-South32 Special Annual Theme Award: Sustainable Energy for All (in recognition of the United Nations 'International Decade of Sustainable Energy for All'). <![CDATA[<b>Big science and human development - what is the connection?</b>]]> http://www.scielo.org.za/scielo.php?script=sci_arttext&pid=S0038-23532018000600011&lng=&nrm=iso&tlng= The rationale for public expenditure and political support for large-scale science infrastructure is commonly underpinned by a universalist logic of big science's benefits. Literature assessing the impact of big science focuses on its contributions towards new fundamental insights about the universe; the development of skills, capabilities, networks, and innovation; and the development of globally transformative technology platforms that in turn make significant impacts on global human development. However, research into the local development impact of big science infrastructure is scarce. In this paper we reflect on the development impact of a big science project at the local level, drawing on the case study of the Square Kilometre Array telescope in South Africa's Karoo region. We find that the universalist logic that appears to apply at the global and national levels does not necessarily apply at the local level, where big science has resulted in human development benefits, but also substantial economic and social costs. On this basis we recommend that big science infrastructures, particularly in marginalised areas of developing countries, require a localised development proposition that takes into account local social complexities on the basis of extensive local engagement. Significance: •A synthetic review is presented of the different causal pathways through which big science may impact on human development. •Analytical distinctions are developed between the human development impacts of big science at the global, national, and local scales. •Considerations are put forward for a developmental agenda for big science facilities, particularly in developing countries <![CDATA[<b>Perverse incentives and the political economy of South African academic journal publishing</b>]]> http://www.scielo.org.za/scielo.php?script=sci_arttext&pid=S0038-23532018000600012&lng=&nrm=iso&tlng= Academic publishing in South Africa attracts a state research incentive for the universities to which the authors are affiliated. The aim of this study was twofold: (1) to examine the composition of the research value chain and (2) to identify the effects of broken links within the chain. The methodology selected was a lived cultural economy study, which was constructed through incorporating dialogue with editors, authors and researchers in terms of my own experience as a journal editor, read through a political economy framework. The prime effect is to exclude journals, especially independent titles, from directly earning publishing incentives. The behaviour of universities in attracting this variable income is discussed in terms of rent-seeking which occurs when organisations and/or individuals leverage resources from state institutions. Firstly, this process commodifies research and its product, publication. Secondly, the value chain is incomplete as it is the journals that are funding publication rather than - in many cases - the research economy funding the journals. Thirdly, authors are seeking the rewards enabled by the incentive attached to measurement systems, rather than the incentive of impacting the discipline/s which they are addressing. Fourthly, the paper discuses some policy and institutional matters which impact the above and the relative costs between open access and subscription models. Editors, journals and publishers are the un- or underfunded conduits that enable the transfer of massive research subsidies to universities and authors, and, in the case of journals, editors' voluntary work is the concealed link in the value chain enabling the national research economy. Significance: • The South African scientific publishing economy is built on a foundation of clay: this economy distorts research impact and encourages universities and academics to commoditise output. <![CDATA[<b>Students' ability to correctly apply differentiation rules to structurally different functions</b>]]> http://www.scielo.org.za/scielo.php?script=sci_arttext&pid=S0038-23532018000600013&lng=&nrm=iso&tlng= The derivative concept is studied in first-year university mathematics. In this study, we focused on students' ability to correctly apply the rules for derivatives of functions with the different structures that they encounter in their university studies. This was done by investigating the online responses of first-year students at the University of KwaZulu-Natal to online quizzes that contributed to their assessment. Based on this investigation, we then interviewed eight students to gain an insight into the thinking behind their responses. We report on the analysis of students' responses to five items on the online quizzes based on the derivative concept. The categories in which those items were based are: condition for existence of derivative at a point; rules for derivatives of standard functions; application of chain rule to different function structures; the application of multiple rules; and application of derivatives to optimise a function. Our findings indicate that students had difficulty in detecting that multiple rules for derivatives were required to differentiate certain types of functions represented in symbolic form. Furthermore, students had difficulty in finding the derivative of a function when more than one application of the chain rule was required. However, there were students who had the ability to apply the rules for derivatives of functions without difficulty. In particular, most of the students were able to correctly recall the differentiation rules for functions with standard structures f(x)=x n, h(x)=e kx and y=[g(x)]n, n = 0 and k is a non-zero constant. Students were also able to correctly apply the chain rule to an exponential function with base e, raised to 4x. The majority of students were able to correctly apply the chain rule together with differentiation rules for logarithmic and exponential (with bases a >1) function structures, and function structures that required the application of the product rule together with the chain rule. Most of the students were able to apply derivatives to optimise a function. Significance: A significant percentage of students who took online quizzes experienced difficulties with applying multiple differentiation rules in the context of a single function. The difficulties stemmed from their inability to detect from the structure of the function which rules should be applied and also the order in which those relevant rules should be applied <![CDATA[<b>The appropriateness of a realist review for evaluating the South African Housing Subsidy Programme</b>]]> http://www.scielo.org.za/scielo.php?script=sci_arttext&pid=S0038-23532018000600014&lng=&nrm=iso&tlng= Conducting meta-reviews of government programmes has become common practice. In South Africa, the national Department of Human Settlements and the national Department of Performance Monitoring and Evaluation recently commissioned a team to review the extent to which the Housing Subsidy Programme had provided assets to municipalities and the poor and whether these assets had helped poor households escape from poverty. A realist approach was employed to conduct the review. We argue that, given the complex nature of housing programmes, the realist review methodology was an appropriate approach to follow in answering the review questions. We explored how the realist review method allowed us to work with the uneven and contested nature of the housing literature and how the review nonetheless enabled elucidation of the factors that had contributed to the expected outcomes. Because this case was the first time that this method was used in a government-commissioned evaluation of housing, there were some practical challenges involved in its use. Some of the challenges were related to the nature of the questions that were asked. At the time of the review, the Department of Human Settlements was in the process of reviewing the 1996 White Paper and, to inform this process, the Housing Subsidy Programme review included a copious number of questions set by the Department of Human Settlements and Department of Performance Monitoring and Evaluation, which made the review rather large and, in some cases, complicated the analysis. In some cases, because the Departments wanted clear-cut answers, the commissioners perceived the theoretical strength of the method, such as offering explanatory instead of conclusive judgement, as a weakness. The paper reveals some limitations of the realist review method for evaluating the multifaceted outcomes of a complex programme, particularly the practical difficulty of dealing with large quantities of data. We do however consider this method to have potential for further reviews. Significance: •Housing research in South Africa is uneven which makes any review process difficult. •The review was unable to offer judgement on the effect that the Housing Subsidy Programme has had on the asset base of the poor. •The review was useful for making clear which factors will help the Programme to achieve the intended outcomes and also for pointing out on what government should focus to build assets for the urban poor. <![CDATA[<b>Productive knowledge, poverty and the entrepreneurial challenges of South African towns</b>]]> http://www.scielo.org.za/scielo.php?script=sci_arttext&pid=S0038-23532018000600015&lng=&nrm=iso&tlng= Stagnant exports per capita and growing poverty in South Africa necessitated an examination of the links between the levels of productive knowledge (measured as enterprise richness), poverty (measured as Enterprise Dependency Indices) and entrepreneurial development (measured as the number of enterprises) in 188 South African towns. Two statistically significant relationships were used to examine groups of towns with different poverty levels: a linear relationship of population size and enterprise numbers, and a power law relationship of population size and enterprise richness. Increased poverty levels severely impact current and future enterprise development, despite the fact that entrepreneurial space develops similarly in wealthy and poor towns. Two broad types of entrepreneurial opportunities were discerned: starting more enterprises of types that are already present in towns, and starting enterprises of types that have not been present before. The latter requires the expansion of productive knowledge. Doubling of productive knowledge (measured as enterprise richness) more than doubles the number of enterprises in towns. The economic growth of towns always requires additional enterprises of types not yet present. This requirement is more stringent in towns with fewer than 100 enterprises, but even in large towns, enterprise growth has a Pareto-like requirement of 20% of new enterprise types. There is evidence of a 'catch-22'-like poverty trap for poor towns: they lack productive knowledge, yet to overcome poverty they need to have productive knowledge. Escaping this trap will be extremely difficult and development plans and policies should heed these findings. Significance: •The link between productive knowledge and the wealth/poverty status of South African towns is quantified. •There is a 'catch-22'-like poverty trap that is difficult to escape in poorer towns. •These findings can assist in plans to combat poverty. <![CDATA[<b>Modelling the length of time spent in an unemployment state in South Africa</b>]]> http://www.scielo.org.za/scielo.php?script=sci_arttext&pid=S0038-23532018000600016&lng=&nrm=iso&tlng= The deteriorating global economic conditions have worsened the unemployment situation, especially among the youth in sub-Saharan Africa. Structural factors such as the length of time spent in unemployment and job sustainability have a considerable effect on the persistence of unemployment for an individual. Non-parametric models were fitted to data consisting of 4.9 million unemployed South Africans to determine the duration dependence and probabilities associated with unemployment. The prospect of finding employment depends on unemployment duration where the rate of finding employment decreases as the length of time in unemployment increases. On average, unemployment exit is observed at lower rates, which translates to people remaining unemployed for longer durations. The human capital of the unemployed deteriorates when more time is spent in an unemployment state, thus making one less employable. Based on the Markov chain processes results, the created jobs are less sustainable because the employed transition back to an unemployment state over time. These findings suggest that the problem of unemployment in South Africa is multidimensional. Significance: •The structural factors associated with unemployment should be modelled to address the unemployment situation in South Africa. •The probability of remaining unemployed increases as the length of stay in unemployment increases. •The lengthy unemployment duration results from a low rate of exiting unemployment. <![CDATA[<b>Potential of marula (<i>Sclerocarya birrea</i> subsp. <i>caffra</i>) waste for the production of vinegar through surface and submerged fermentation</b>]]> http://www.scielo.org.za/scielo.php?script=sci_arttext&pid=S0038-23532018000600017&lng=&nrm=iso&tlng= Although there is an abundance of indigenous fruits in South Africa, knowledge of their potential uses is mainly restricted to within communities. In this study, marula fruit-processing waste by-products (fruit pulp residue and skin) were used as substrates in surface culture and submerged fermentation methods to produce vinegar (acetic acid) using spontaneous and starter culture techniques. The study revealed the possibility of producing vinegar through both methods of fermentation, with yields of acetic acid ranging between 41 000 mg/L and 57 000 mg/L (surface culture method) and between 41 000 and 54 000 mg/L (submerged culture method). Furthermore, the physicochemical property analyses revealed marula vinegar to be a potential source of bioactive compounds (total phenolics 0.289-0.356 mg/L GAE and total flavonoids 0.146-0.153 mg/L CAE) which displayed a potent antiradical activity against DPPH•: 78.85% for surface culture and 73.03% submerged culture, respectively. The sensory panel recommended application of the vinegar in products such as salad dressing and mayonnaise. Finally, we have demonstrated that the surface culture method using the inoculation technique is more suitable for the production of high-quality vinegar, with possible consideration for commercialisation. Significance: •Marula fruit has high economic importance for South Africa, particularly for the Limpopo Province. •Marula waste can be a source of bioactive compounds, yet comparatively little is reported on the potential use of the waste to produce vinegar. •Self-development of communities through viable and easy to produce commodities from marula fruit needs to be implemented and prioritised in the Limpopo Province. <![CDATA[<b>Recent emergence of CAT5 tropical cyclones in the South Indian Ocean</b>]]> http://www.scielo.org.za/scielo.php?script=sci_arttext&pid=S0038-23532018000600018&lng=&nrm=iso&tlng= The IBTrACS global best track data set endorsed by the World Meteorological Organization provides a valuable global record of tropical cyclone genesis, track and intensity, and spans 1842 to the present. The record is significantly more robust from the late 1970s onwards, as it is supported by satellite imagery. These records indicate that the first tropical cyclone in the South Indian Ocean to intensify to CAT5 status did so in 1994. This date is significantly later than the first CAT5 storms recorded in the IBTrACS database for the Atlantic Ocean (1924) and the North Pacific (1951) recorded from ship records, and half a decade later than those of the North Indian Ocean (1989) and South Pacific (1988), captured from satellite imagery. Following this late emergence, in the period 1990-2000, eight CAT5 tropical cyclones were recorded for the South Indian Ocean. A further four have been recorded for the period 2010-2015. This recent emergence of tropical cyclones attaining category five intensity in the South Indian Ocean is of significance for the forecasting of tropical cyclone landfall and the anticipation of storm damage for the developing economies that characterise the region. Although an increase in tropical cyclone intensity is frequently projected under global climate change scenarios, the dynamics for the South Indian Ocean have remained poorly understood. Notable are early results indicating an increased frequency and poleward migration of these CAT5 storms, concurrent with a poleward migration in the position of the 26.5 °C, 28 °C and 29 °C sea surface temperature isotherms in the South Indian Ocean. Significance: •Category 5 tropical cyclones, the strongest category of storms, have only recently emerged in the South Indian Ocean. Since 1989, their frequency of occurrence has increased. This increase poses a heightened risk of storm damage for the South Indian Ocean Island States and the countries of the southern African subcontinent as a result of the strong winds, heavy rainfall and storm surges associated with these storms, and the large radial extent at category 5 strength. <![CDATA[<b>Applying the water-energy-food nexus to farm profitability in the Middle Breede Catchment, South Africa</b>]]> http://www.scielo.org.za/scielo.php?script=sci_arttext&pid=S0038-23532018000600019&lng=&nrm=iso&tlng= The water-energy-food nexus has emerged as a useful concept to understand the multiple interdependencies that exist between the water, energy and food sectors. The nexus is an ambitious attempt to work across disciplines and scales to understand the workings of these complex systems. It is, however, criticised for being more of a general framework than a practical methodology because of the vast amount of data it would need to make real-life contributions to sustainable development. We show how the nexus approach, when used within a farm budget model, can transform the problem focus in water governance. By changing the relationship among water, energy and food production of a farm, profitability is significantly changed. The water-energy-food nexus debate is discussed within the context of the South African water sector, particularly the Breede River Catchment. Working from within the farm budget model, we demonstrate the impact of moving from an irrigation canal system that requires electricity for pumping, to a gravity-fed piped irrigation system in the Middle Breede River. The finding is that the water-energy-food nexus has the potential to unlock groundbreaking solutions to complex problems in agricultural water management when used in appropriate modelling systems. Significance: •The water-energy-food nexus approach can lead to an entirely new framing of water governance problems and therefore solutions to these problems. •The water-energy-food nexus when used in farm budget models can identify ways of altering farm profitability. •By addressing the energy cost of farming through an irrigation pipeline system in parts of the Breede Catchment Area, farm profitability could significantly increase. •A gravity-fed closed pipeline system in parts of the Breede River can improve water availability and reduce farm and management costs. <![CDATA[<b>Remains of a barn owl (<i>Tyto alba</i>) from the Dinaledi Chamber, Rising Star Cave, South Africa</b>]]> http://www.scielo.org.za/scielo.php?script=sci_arttext&pid=S0038-23532018000600020&lng=&nrm=iso&tlng= Excavations during November 2013 in the Rising Star Cave, South Africa, yielded more than 1550 specimens of a new hominin, Homo naledi. Four bird bones were collected from the surface of the Dinaledi Chamber during the first phase of the initial excavations. Although mentioned in the initial geological and taphonomic reports, the bird remains have not been formally identified and described until now. Here we identify these remains as the extant barn owl (Tyto alba) which is today common in the region and which is considered to have been an important agent of accumulation of microfaunal remains at many local Plio-Pleistocene sites in the Cradle of Humankind. Based on the greatest length measurement and breadth of the proximal articulation of the tarsometatarsus specimen, it is suggested that a single (female) individual is represented, despite the small sample sizes available for comparison. Although it is unclear how the remains of this female owl came to be accumulated in the remote Dinaledi Chamber, we suggest several possible taphonomic scenarios and hypothesise that these remains are not directly associated with the Homo naledi remains. Significance: •Owl bones from the Dinaledi Chamber are the only other macro-vertebrate remains from this Chamber. •The other remains discovered are that of more than 15 individuals of the enigmatic Homo naledi. •The remains of the Dinaledi Chamber owl further our understanding of the contents of the important material contained within the Dinaledi system as they are the only more recent fossils to be recovered from this area of the Rising Star Cave system and are therefore important in and of themselves as an indicator that more proximal parts of the Rising Star Cave system have been suitable for use by barn owls at greater time depths than the present. <![CDATA[<b>Hominin cranial fragments from Milner Hall, Sterkfontein, South Africa</b>]]> http://www.scielo.org.za/scielo.php?script=sci_arttext&pid=S0038-23532018000600021&lng=&nrm=iso&tlng= The Sterkfontein Caves site is one of the richest early hominin localities in Africa. In addition to significant fossil assemblages from Members 2 and 4 of the Sterkfontein Formation, recent excavations have revealed hominin-bearing sedimentary deposits in the lesser-known Milner Hall. We describe two hominin cranial fragments excavated from the Milner Hall in 2015 and present the results of a high-resolution microtomographic-based approach to diagnosing the anatomical and taxonomical origin of these specimens. Based on external morphology, StW 671 and StW 672 are identified as frontal and occipital fragments, respectively. Our non-invasive bi-dimensional quantitative investigation of the two cranial fragments reveals a mean cranial thickness of 8.8 mm for StW 671 and of 5.6 mm for StW 672, and a contribution of the diploic layer to the cumulative cranial thickness that is less than 50%. While the mean cranial thickness of StW 671 falls within the range for Homo, the relative proportion of the diploë in both StW 671 and StW 672 is lower than that found in Australopithecus (>60%) and extant humans (>50%). Accordingly, in terms of both cranial thickness and inner structural organisation, the Milner Hall hominins combine derived and unique traits, consistent with the condition of other postcranial and dental material already described from the deposit. Moreover, our study opens interesting perspectives in terms of analysis of isolated cranial fragments, which are abundant in the hominin fossil record. Significance: •The Sterkfontein Caves have widely contributed to our understanding of human evolution. •Besides the well-known Members 4 and 2, where the iconic 'Mrs Ples' and 'Little Foot' have been found, in this study we suggest that the Milner Hall locality represents an additional, stratigraphically associated source of not only fossil hominins, but also Oldowan stone tools. •In particular, we describe for the first time two cranial fragments, StW 671 and StW 672, identified as frontal and occipital bones, respectively. •Our microtomographic-based analysis of these materials reveals some affinities with Homo combined with unique characters. •In this context, our study suggests an intriguing mosaicism consistent with the description of the two fossil hominins found in the Milner Hall.