List of Titles

'We throw away our books': Students’ reading practices and identities

- O'Shea, Cathy, McKenna, Sioux, Thomson, Carol I

Authors: O'Shea, Cathy , McKenna, Sioux , Thomson, Carol I
Date: 2019
Subjects: To be catalogued
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/187128 , vital:44570 , xlink:href="https://doi.org/10.1016/j.linged.2018.11.001"
Description: The aim of this research was to understand university students’ self-reported reading practices. The students attended the University of Fort Hare in South Africa, a historically black institution in a rural and under-resourced setting. A framework of New Literacy Studies (NLS) was used to understand students’ self-reported reading practices and the links between these and their identities. Tools provided by Gee, 2005, Gee, 2011 were applied to conduct a CDA of focus group discussions. In the ‘We Blacks’ Discourse, interviewees ‘othered’ the idea of reading as not being culturally valued. It was closely allied to the ‘Resistance to Reading’ Discourse, as participants explained that they tended to disregard books and did not enjoy leisure reading. The ‘Better Than Us’ discourse was drawn upon to suggest that reading was associated with attitudes of superiority. These discourses tended to homogenise class and other differences between black students and indicated the ways in which their experiences made adopting academic identities difficult. The analysis suggests that the racism of the past continues to impact students’ reading identities. The article concludes that the effects of these and related discourses require a response across the education sector, and transformative pedagogies might be needed in higher education.
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Date Issued: 2019

1H NMR-based kinetic and theoretical studies of the simultaneous formation of two discrete rotameric systems of a novel difenchyl sulfite ester

- Singh, Alicia, Kaye, Perry T, Lobb, Kevin A

Authors: Singh, Alicia , Kaye, Perry T , Lobb, Kevin A
Date: 2017
Subjects: To be catalogued
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/447925 , vital:74684 , xlink:href="https://doi.org/10.1016/j.tet.2017.10.059"
Description: Attempted repetition of a reported synthesis of fenchene from fenchol has afforded, in high overall yield, a mixture shown by spectroscopic and elemental analysis to comprise a pair of discrete rotameric systems of a novel 2-endo-2′-endo-difenchyl sulfite ester. The kinetics of the formation of these dimeric rotameric systems (I and II) has been explored experimentally, using 1H NMR spectroscopic analysis, and theoretically at molecular and quantum mechanical levels. Construction of a theoretical model has permitted calculation of rate constants for each of the steps, while modelling of the transition state complexes corresponding to the rate-determining steps for the formation of the rotameric systems I and II has revealed their independent access to further sets of interconverting rotamers.
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Date Issued: 2017

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A colorimetric probe for dopamine based on gold nanoparticles-electrospun nanofibre composite

- Ngomane, Nokuthula, Torto, Nelson, Krause, Rui W M, Vilakazi, Sibulelo

Authors: Ngomane, Nokuthula , Torto, Nelson , Krause, Rui W M , Vilakazi, Sibulelo
Date: 2015
Subjects: To be catalogued
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/195407 , vital:45562 , xlink:href="https://doi.org/10.1016/j.matpr.2015.08.036"
Description: An easily prepared solid state colorimetric probe for detecting the neurotransmitter dopamine (DA) was developed. The probe, in the form of an electrospun Nylon−6 (N6) nanofibre with embedded un−functionalized gold nanoparticles (UF−AuNPs) produces a clear colour change in the presence of a DA that is detectable by the naked eye. Characterisation of the nanofibre using UV/vis spectroscopy and electron microscopy (TEM) confirmed the formation of the AuNPs in the polymer solution, and that the AuNPs were completely encapsulated within the composite nanofibres before exposure to the analytes. The probe exhibited very high sensitivity towards DA resulting in colour change of the composite fibres from purple to navy blue/black even under low concentrations of DA. The probe was also selective to DA since the colour remained unchanged in the presence of commonly encountered interfering species such as ascorbic acid, uric acid, catechol, epinephrine and norepinephrine. Moreover, the colour change was observed rapid, occurring either immediately on contact with higher concentrations (5 x10−4 M) or within about 3−5 min for the lower concentrations (e.g. 5 x10−7 M). Since this probe does not require the use of any instruments, and is both rapid and stable over time, it can be applied in the field by an inexperienced person.
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Date Issued: 2015

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A comparative photophysicochemical study of mono substituted phthalocyanines grafted onto silica nanoparticles

- Fashina, Adebayo, Antunes, Edith M, Nyokong, Tebello

Authors: Fashina, Adebayo , Antunes, Edith M , Nyokong, Tebello
Date: 2014
Subjects: To be catalogued
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/193844 , vital:45399 , xlink:href="https://doi.org/10.1142/S1088424614500138"
Description: In this study, we report on the covalent linking of carboxylic acid functionalized silica nanoparticles with zinc phthalocyanine mono-substituted non-peripherally and peripherally with either a 4-amino phenoxy (1, peripheral and 2, non-peripheral) or an amino group (3 peripheral). The grafting is achieved via the formation of an amide bond between the carboxylic acid of the silica nanoparticles and the amino group of the phthalocyanine complexes. The hybrid nanoparticles retained the amorphous nature of silica nanoparticles after conjugation. A slight decrease in fluorescence and a general improvement in triplet quantum yields compared to free Pcs were observed. Triplet lifetimes for 2-SiNPs and 3-SiNPs also improved when compared to the free phthalocyanine. The changes in singlet oxygen quantum yields upon conjugation were minimal.
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Date Issued: 2014

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A comparison of anthropogenic and elephant disturbance on Acacia xanthophloea (fever tree) populations in the Lowveld, South Africa

- Botha, Jenny, Witkowski, Ed T F, Shackleton, Charlie M

Authors: Botha, Jenny , Witkowski, Ed T F , Shackleton, Charlie M
Date: 2002
Subjects: To be catalogued
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/181629 , vital:43753 , xlink:href="https://doi.org/10.4102/koedoe.v45i1.10"
Description: Acacia xanthophloea (the ‘fever tree’) is a popular medicinal species that is traded widely in South Africa. Although it occurs throughout southern Africa, there is increasing pressure on its riverine and marshy habitats. This study compares the impact of harvesting on an A. xanthophloea population located on private land near Komatipoort, Mpumalanga, with two protected populations situated within the Kruger National Park. The densities of the harvested and protected populations were similar (84±8 trees/ha and 85±20 trees/ha, respectively). There were fluctuations in the quotients between frequencies of trees in successive diameter classes, which is common in savanna where high levels of fire, mega-herbivore and anthropogenic disturbance are experienced. The extent of stem damage (stripping of bark and breakage) by elephants in the protected area was significantly higher than the extent of harvesting on private land, although the degree of damage was relatively low, with only 7 % of the populations having been damaged at rates >26 %. The degree of harvesting on private land was relatively low, with the majority of trees having been harvested at rates of less than 10 % of the stem below 2 m. Despite this, ringbarking had occurred (4 %). The basal diameters and heights were significantly lower in the protected population than in the harvested one, suggesting that over time elephant impact was the more severe disturbance. Acacia xanthophloea exhibited high resilience to disturbance, with all the elephant damaged trees and harvested individuals surviving. However, the mean bark thickness measured in local markets (6.3±1.4 mm) was significantly lower than that measured in either the harvested (12.4±1.0 mm) or the KNP (10.3±0.8 mm) populations. As harvesters tend to select the largest individuals in a population to maximise their financial returns, this could mean that smaller individuals are being harvested, and/or bark is not being given sufficient time to grow back after harvesting. Acacia xanthophloea outside protected areas thus need to be monitored and the management improved, preferably in conjunction with the resource users. In addition, traditional healers, those selling medicinal plants and other members of the community need to continue to be encouraged to cultivate this fast growing species.
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Date Issued: 2002

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A reflection on the use of case studies as a methodology for social learning research in sub Saharan Africa

- Cundill, Georgina, Lotz-Sisitka, Heila, 1965-, Mukute, Mutizwa, Ali, Million Belay, Shackleton, Sheona E, Kulundu-Bolus, Injairu M

Authors: Cundill, Georgina , Lotz-Sisitka, Heila, 1965- , Mukute, Mutizwa , Ali, Million Belay , Shackleton, Sheona E , Kulundu-Bolus, Injairu M
Date: 2014
Subjects: To be catalogued
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/182832 , vital:43884 , xlink:href="https://doi.org/10.1016/j.njas.2013.04.001"
Description: A recent review has highlighted that the methodology most commonly employed to research social learning has been the individual case study. We draw on four examples of social learning research in the environmental and sustainability sciences from sub-Saharan Africa to reflect on possible reasons behind the preponderance of case study research in this field, and to identify common elements that may be significant for social learning research more generally. We find that a common interest in change oriented social learning, and therefore processes of change, makes case studies a necessary approach because long term process analyses are required that are sensitive to social-ecological contexts. Common elements of the examples reflected upon included: a focus on initiating, tracking and/or understanding a process of change toward sustainability; long term research; an action research agenda that involves reflecting on data with research participants; and temporal, process based analysis of data coupled with in-depth theoretical analysis. This paper highlights that there is significant scope for exploratory research that compares case studies of social learning research to generate a deeper understanding of social learning processes, and their relationship to human agency and societal change.
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Date Issued: 2014

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A study on the morphology of thin copper films on para-aramid yarns and their influence on the yarn’s electro-conductive and mechanical properties

- Schwarz, Anne, Hakuzimana, Jean, Westbroek, Philippe, Mey, Gilbert De, Priniotakis, Georgios, Nyokong, Tebello, Langenhove, Lieva Van

Authors: Schwarz, Anne , Hakuzimana, Jean , Westbroek, Philippe , Mey, Gilbert De , Priniotakis, Georgios , Nyokong, Tebello , Langenhove, Lieva Van
Date: 2012
Subjects: To be catalogued
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/243487 , vital:51157 , xlink:href="https://doi.org/10.1177/0040517511431291"
Description: The latest technological advances in new materials and devices enabled wearable systems to be created by utilizing textile solutions. These solutions require electro-conductive yarns as a basic component. Although the production of electroconductive yarn is widely reported, research is still necessary to characterize them to advance their electro-conductive and mechanical properties. Hence, we served this need and characterized copper-coated para-aramid yarns produced by an in-house developed electroless deposition method. In this paper we present our investigation on the yarn’s copper layer characteristics after deposition. Furthermore, we looked, in depth, at the yarn’s electro-conductive properties before and after washing as well as their mechanical properties before and after copper deposition. We found a dependency of the copper layer morphology on its deposition time. This is directly correlated to the resulting layer thickness and hence to the yarn’s electro-conductive properties, demonstrating the autocatalytic nature of the coating process. Above that, the electro-conductive properties of the coated yarn linearly decrease with washing cycles. Furthermore, the copper coating impairs the yarn’s mechanical properties decreasing its specific stress at break by 30%.
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Date Issued: 2012

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A white man in exile

- Krueger, Anton

Authors: Krueger, Anton
Date: 2011
Subjects: To be catalogued
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/229459 , vital:49677 , xlink:href="https://doi.org/10.1080/10137548.2011.636974"
Description: This article explores intersections between understandings of masculinity and nationalism. Etymologically, ‘patriotism’ refers to a love for a fatherland and a patriarchal order; it includes notions of loyalty, honour and a range of qualities often associated with conceptions of masculinity. But if gender remains fixed to these normative constructions, what happens to one’s sense of masculine identity when the national state changes? My interest lies in exploring how white South African men have been repositioned in terms of a shift in their gendered identification, with a reflection on the possibly tragic consequences of maintaining an overly rigid gender role identification. As long as masculinity is embedded within nationalism, it will be caught up within a defensive reactive mode which can turn self-destructive. In order to explore these ideas the article employs as its central metaphor the character of Dawid Olivier, who is the protagonist of Athol Fugard’s Sorrows and Rejoicings (2002).
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Date Issued: 2011

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Addressing the red flags in cochineal identification: The use of molecular techniques to identify cochineal insects that are used as biological control agents for invasive alien cacti

- van Steenderen, Clarke J M, Paterson, Iain D, Edwards, Shelley, Day, Michael D

Authors: van Steenderen, Clarke J M , Paterson, Iain D , Edwards, Shelley , Day, Michael D
Date: 2021
Subjects: To be catalogued
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/423282 , vital:72044 , xlink:href="https://doi.org/10.1016/j.biocontrol.2020.104426"
Description: Invasive Cactaceae cause considerable damage to ecosystem function and agricultural practices around the world. The most successful biological control agents used to combat this group of weeds belong to the genus Dactylopius (Hemiptera: Dactylopiidae), commonly known as ‘cochineal’. Effective control relies on selecting the correct species, or in some cases, the most effective intraspecific lineage, of cochineal for the target cactus species. Many of the Dactylopius species are so morphologically similar, and in the case of intraspecific lineages, identical, that numerous misidentifications have been made in the past. These errors have resulted in failed attempts at the biological control of some cactus species. This study aimed to generate a multi-locus genetic database to enable the accurate identification of dactylopiids. Genetic characterization was achieved through the nucleotide sequencing of three gene regions (12S rRNA, 18S rRNA, and COI) and two inter-simple sequence repeats (ISSR). Nucleotide sequences were very effective for species-level and D. tomentosus lineage-level identification, but could not distinguish between the two lineages within D. opuntiae commonly used for biological control of various Opuntia spp. Fragment analysis through the use of ISSRs successfully addressed this issue. This is the first time that a method has been developed that can distinguish between these two D. opuntiae lineages. Using the methods developed in this study, biological control practitioners can ensure that the most effective agent species and lineages are used for each cactus target weed, thus maximizing the level of control.
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Date Issued: 2021

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Adsorption and separation of platinum and palladium by polyamine functionalized polystyrene-based beads and nanofibers

- Fayemi, Omolola E, Ogunlaja, Adeniyi S, Kempgens, Pierre F M, Antunes, Edith M, Torto, Nelson, Nyokong, Tebello, Tshentu, Zenixole R

Authors: Fayemi, Omolola E , Ogunlaja, Adeniyi S , Kempgens, Pierre F M , Antunes, Edith M , Torto, Nelson , Nyokong, Tebello , Tshentu, Zenixole R
Date: 2013
Subjects: To be catalogued
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/241694 , vital:50961 , xlink:href="https://doi.org/10.1016/j.mineng.2013.06.006"
Description: Adsorption and separation of platinum and palladium chlorido species (PtCl62- and PdCl42-) on polystyrene beads as well as nanofibers functionalized with ammonium centres based on ethylenediamine (EDA), diethylenetriamine (DETA), triethylenetetramine (TETA) and tris-(2-aminoethyl)amine (TAEA) are described. The functionalized sorbent materials were characterized by microanalysis, SEM, XPS, BET and FTIR. The surface area of the functionalized fibers was in the range 69–241 m2/g while it was 73–107 m2/g for the beads. The adsorption and loading capacities of the sorption materials were investigated using both the batch and column studies at 1 M HCl concentration. The adsorption studies for both PtCl62- and PdCl42- on the different sorbent materials fit the Langmuir isotherm with R2 values >0.99. The highest loading capacity of Pt and Pd were 7.4 mg/g and 4.3 mg/g respectively for the nanofiber sorbent material based on ethylenediamine (EDA) while the beads with ethylenediamine (EDA) gave 1.0 mg/g and 0.2 mg/g for Pt and Pd respectively. Metals loaded on the sorbent materials were recovered by using 3% m/v thiourea solution as the eluting agent with quantitative desorption efficiency under the selected experimental conditions. Separation of platinum from palladium was partially achieved by selective stripping of PtCl62- with 0.5 M of NaClO4 in 1.0 M HCl while PdCl42- was eluted with 0.5 M thiourea in 1.0 M HCl. Separation of platinum from iridium and rhodium under 1 M HCl concentration was successful on triethylenetriamine (TETA)-functionalized Merrifield beads. This material (M-TETA) showed selectivity for platinum albeit the low loading capacity.
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Date Issued: 2013

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Agent-based model development of a complex socio-ecological system: Methods for overcoming data and domain limitations

- James, C. L, Bradshaw, Karen L

Authors: James, C. L , Bradshaw, Karen L
Date: 2023
Subjects: To be catalogued
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/440189 , vital:73755 , xlink:href="https://doi.org/10.1016/j.ecoinf.2023.102224"
Description: Agent-based models (ABMs) are appropriate tools for modelling socio-ecological systems due to their ability to handle complexity. However, development of such models is often an intensive process. There are many tutorials on the general methods and steps in ABM development but there are not necessarily practical details on how to overcome certain challenges. Honeybush (Cyclopia spp.), a kind of fynbos vegetation found in the Western and Eastern Cape mountains, is an important ecological and agricultural product in South Africa. It is considered a complex system due to its variability and unpredictability. The honeybush tea industry faces the challenge of meeting emerging market demands while maintaining sustainable harvesting practices, in the midst of an uncertain future due to climate change. We created a prototype model, HoneybushModel, using the MARS framework, a C# multi-agent simulation toolkit. The model was validated using historic data. Whilst outlining the development processes used to create the Honeybush Model, this paper provides a methodology for the development of such models and demonstrates techniques for addressing data, domain and framework limitations. The implemented model also acts as a case study for similar systems that could be modelled using an ABM.
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Date Issued: 2023

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Argumentative and trustworthy scholars

- McKenna, Sioux, Boughey, Chrissie

Authors: McKenna, Sioux , Boughey, Chrissie
Date: 2014
Subjects: To be catalogued
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/187216 , vital:44580 , xlink:href="https://doi.org/10.1080/13562517.2014.934351"
Description: Research-intensive universities, such as the Russell Group in the UK, the Ivy League Colleges in the USA and the Sandstone Universities in Australia, enjoy particular status in the higher education landscape. They are, however, also often associated with social elitism and selectivity, and this has led to critique as higher education systems seek to widen access. This article looks at how academic staff are discursively constructed in five such institutions in South Africa through an analysis of documentation submitted as part of a national review. Three interrelated discourses are identified: a discourse of ‘staff as scholars’ whereby research is privileged over teaching, a discourse of ‘academic argumentation’ whereby a critical disposition is valued and is called upon by academics to resist development initiatives and a discourse of ‘trust’ whereby it is assumed that academics share a value system and should thus be trusted to undertake quality teaching without interference.
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Date Issued: 2014

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Behavior of palladium nanoparticles in the absence or presence of cobalt tetraaminophthalocyanine for the electrooxidation of hydrazine

- Maringa, Audacity, Nyokong, Tebello

Authors: Maringa, Audacity , Nyokong, Tebello
Date: 2014
Subjects: To be catalogued
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/189796 , vital:44932 , xlink:href="https://doi.org/10.1002/elan.201400028"
Description: We report on the electrodeposition of palladium nanoparticles (PdNPs) on a glassy carbon electrode (GCE) and onto a poly-CoTAPc-GCE (CoTAPc=cobalt tetraamino phthalocyanine) surface. The electrodes are denoted as PdNPs-GCE and PdNPs/poly-CoTAPc-GCE, respectively. PdNPs/poly-CoTAPc-GCE showed the best activity for the oxidation of hydrazine at the lowest potential of −0.28 V and with the highest currents. The results were further supported by electrochemical impedance spectroscopy (EIS) which showed that there was less resistance to charge transfer for PdNPs/poly-CoTAPc-GCE compared to PdNPs-GCE. The catalytic rate constant for hydrazine oxidation was 6.12×108 cm3 mol−1 s−1 using PdNPs/poly-CoTAPc-GCE.
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Date Issued: 2014

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Best of both worlds: The thermal physiology of Hydrellia egeriae, a biological control agent for the submerged aquatic weed, Egeria densa in South Africa

- Smith, Rosali, Coetzee, Julie A, Hill, Martin P

Authors: Smith, Rosali , Coetzee, Julie A , Hill, Martin P
Date: 2022
Subjects: To be catalogued
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/417913 , vital:71494 , xlink:href="https://doi.org/10.1007/s10526-022-10142-w"
Description: The submerged aquatic weed, Egeria densa Planch. (Hydrocharitaceae) or Brazilian waterweed, is a secondary invader of eutrophic freshwater systems in South Africa, following the successful management of floating aquatic weeds. In 2018, the leaf and stem-mining fly, Hydrellia egeriae Rodrigues-Júnior, Mathis and Hauser (Diptera: Ephydridae), was released against E. densa, the first agent released against a submerged aquatic weed in South Africa. During its life stages, the biological control agent is exposed to two environments, air and water. The thermal physiology of both life stages was investigated to optimize agent establishment through fine-tuned release strategies. The thermal physiological limits of H. egeriae encompassed its host plant’s optimal temperature range of 10 to 35 °C, with lower and upper critical temperatures of 2.6 to 47.0 °C, lower and upper lethal temperatures of − 5.6 and 40.6 °C for adults, and − 6.3 to 41.3 °C for larvae. Results from development time experiments and degree-day accumulation showed that the agent is capable of establishing at all E. densa sites in South Africa, with between 6.9 and 8.3 generations per year. However, cold temperatures (14 °C) prolonged the agent’s development time to three months, allowing it to only develop through one generation in winter. Predictions obtained from laboratory thermal physiology experiments corroborates field data, where the agent has established at all the sites it was released.
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Date Issued: 2022

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Bioequivalence assessment of generic products an innovative South African approach

- Walker, Roderick B, Kanfer, Isadore, Skinner, Michael F

Authors: Walker, Roderick B , Kanfer, Isadore , Skinner, Michael F
Date: 2006
Subjects: To be catalogued
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/184256 , vital:44194 , xlink:href="https://doi.org/10.1080/10601330500534014"
Description: Concurrent with the implementation of new legislation mandating Generic Substitution in South Africa, a new set of guidelines for bioavailability and bioequivalence have been published. Since one of the main objectives of the new legislation in South Africa relating to Generic Substitution is to ensure that medicines of high quality, safety, and efficacy are made more accessible and more affordable to the wider public, the need to speed up approval of such multi-source products has become a regulatory priority. In order to facilitate this process, various bioequivalence issues have been addressed including important issues such as the acceptance criteria and associated bioequivalence intervals, use of a foreign reference product and the issue of assessing highly variable drugs (HVDs). In addition, dispensations have been made with respect to food effect assessment and variability relating to genetic polymorphism in drug metabolism (genotyping/phenotyping). Furthermore, the use of “old” biostudies submitted in support of an application is subject to expiry date. Acceptance of appropriate data requires that specific criteria such as Cmax and AUC, in addition to the usual considerations, also meet the limits specified by the particular registration authority of the country where such products are intended to be marketed. Generally, these limits require that the 90% confidence interval (CI) for AUC and Cmax test/reference ratios lies within the acceptance interval of 0.80–1.25 calculated using log-transformed data. While such acceptance criteria are, in general, ubiquitous, some differences in acceptance criteria do exist between various countries. The new guidelines for bioavailability/bioequivalence studies developed by the South African regulatory authority, the Medicines Control Council (MCC), makes provision for highly variable drugs and the use of a non-South African reference product. The MCC requires that the acceptance criterion for Cmax ratios be set at 0.75–1.33 while maintaining AUC ratios at 0.80–1.25 using a 90% CI. Furthermore, provision is made to apply scaling based on average bioequivalence assessment and, as an interim measure, consideration has also been given to the use of a foreign reference product provided that equivalence between that product and the innovator product currently available on the South African market can be shown using in vitro testing.
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Date Issued: 2006

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Characterisation of the dietary relationships of two sympatric hake species, Merluccius capensis and M. paradoxus, in the northern Benguela region using fatty acid profiles

- Iitembu, Johannes A, Richoux, Nicole B

Authors: Iitembu, Johannes A , Richoux, Nicole B
Date: 2016
Subjects: To be catalogued
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/456010 , vital:75475 , xlink:href="https://doi.org/10.2989/1814232X.2015.1115778"
Description: The two sympatric species of Cape hake, Merluccius capensis and M. paradoxus, have been the main targets of bottom-trawl fisheries off Namibia for several decades. The feeding ecology of these hakes has been studied mainly using stomach content analyses and thus there remain some gaps in our knowledge about food assimilated over the longer term. In this study, we used fatty acid (FA) profiles to characterise the dietary relationships of M. capensis and M. paradoxus. Muscle samples from hake (n=110) and their known prey (n=68) were collected during trawl surveys off Namibia during 2011. Significant differences between the neutral FA profiles of the hake populations were detected in December 2011 but not in January 2011, an indication of temporal variations in diet and resource partitioning. Comparisons of the neutral FAs in hake and the total FAs of potential prey showed no clear trophic connections, with the exception of flying squid Todarodes sagittatus, which had FA profiles very similar to those of M. paradoxus in December 2011. Our results highlight the complex and temporally shifting relationships that exist between hake and the large pool of prey available to them, and between the two hake species that overlap in their feeding habits and distribution within the highly productive Benguela Current region.
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Date Issued: 2016

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Characterization of conjugates of NaYF4

- Watkins, Zane, Uddin, Imran, Britton, Jonathan, Nyokong, Tebello

Authors: Watkins, Zane , Uddin, Imran , Britton, Jonathan , Nyokong, Tebello
Date: 2017
Subjects: To be catalogued
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/238132 , vital:50589 , xlink:href="https://doi.org/10.1016/j.molstruc.2016.10.011"
Description: NaYF4:Er/Yb/Gd upconversion nanoparticles (UCNP) capped with amino groups were covalently attached to chloro aluminium tetrasulphonated phthalocyanine (ClAlTSPc) and chloro aluminium tetracarboxy phthalocyanine (ClAlTCPc). The conjugates were characterized using different techniques such as infrared spectroscopy (IR), X-ray photoelectron spectroscopy (XPS), and transmission electron microscopy (TEM). There was a decrease in the intensity of fluorescence emission spectra of the UCNPs at 658 nm in the presence of the phthalocyanines. This decrease indicates an energy transfer between the donor UCNP and conjugated accepting phthalocyanine (Pc), due to Förster resonance energy transfer (FRET). FRET efficiencies of 18% and 21% for ClAlTSPc and ClAlTCPc, respectively, were obtained. Oxygen generation by ClAlTSPc following FRET was proved.
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Date Issued: 2017

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Chemical Profiling, Toxicity and Anti-Inflammatory Activities of Essential Oils from Three Grapefruit Cultivars from KwaZulu-Natal in South Africa

- Miya, Gugulethu, Oyedeji, Opeoluwa, Gondwe, Mavuto, Oyedeji, Adebola

Authors: Miya, Gugulethu , Oyedeji, Opeoluwa , Gondwe, Mavuto , Oyedeji, Adebola
Date: 2021-6
Subjects: South Africa Citrus paradisi grapefruit essential oil toxicity anti-inflammatory Article
Language: English
Type: text , article
Identifier: http://hdl.handle.net/11260/6479 , vital:46408 , ("https://DOI:10.3390/molecules26113387")
Description: Introduction: This case report discusses the successful use of an improvised bubble continuous positive airway pressure (CPAP) apparatus made using items commonly available in a poorly resourced district hospital. Case presentation: A 64-year-old female with no co-morbidities presented with respiratory failure due to pulmonary tuberculosis and was not accepted into the regional Intensive Care Unit (ICU) on referral. She required 8 days of improvised bubble CPAP to maintain adequate oxygen saturation before weaning and eventual discharge. Discussion: Improvised bubble CPAP is commonly used in neonatal care in developing countries and well described in literature however, there are no reports of its successful use in adult patients. In the absence of access to ICU or other Non-invasive ventilation (NIV) equipment, improvised bubble CPAP may provide some therapeutic benefit.
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Date Issued: 2021-6

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Cloud computing adoption: Strategies for Sub-Saharan Africa SMEs for enhancing competitiveness

- Adane, Martin

Authors: Adane, Martin
Date: 2018
Subjects: business intelligence small businesses business planning Article
Language: English
Type: text , article
Identifier: http://hdl.handle.net/11260/6862 , vital:51101 , xlink:href="https://doi.org/10.1080/20421338.2018.1439288"
Description: Small and medium-sized enterprises (SMEs) need to design and implement strategies for adopting new technologies as a competitive tool for maintaining their competitive advantage and cloud computing is at its peak. Since its emergence, there has been a surge in the adoption of cloud computing with research into its adoption primarily concentrated on bigger firms. However, a major characteristic of cloud computing is the anticipated possibilities it holds for SMEs. This paper primarily explores cloud computing adoption strategies for SMEs operating in Sub-Saharan Africa. Using a mixed method approach, a sample of 261 respondents and 11 SMEs was respectively used for the quantitative and qualitative stages of the research. The results reveal that, even though SMEs have their unique expectations for adopting cloud computing, they were of the consensus that elements of an adoption strategy should include adoption goals, a roadmap, and considerations. The paper makes specific recommendations to SMEs to develop adoption strategies that meet their specific needs if they expect cloud computing to play a stronger role to support more strategic initiatives to grow their businesses and improve customer experience.
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Date Issued: 2018

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