Showing items 41 - 60 of 786

Your selections:

The past meets the present: exploring the biogeography of extant plecoptera of South Africa with reference to ancient middle permian fossil forms from the Onder Karoo locality near Sutherland

  • Authors: Kirkaldy, Benjamin Puleng
  • Date: 2020
  • Subjects: Stoneflies, Fossil -- South Africa -- Northern Cape , Palaeopteron -- South Africa -- Northern Cape , Stoneflies -- Evolution , Insects, Fossil -- South Africa -- Northern Cape , Paleoentomology , Paleoentomology -- South Africa -- Northern Cape
  • Language: English
  • Type: Thesis , Masters , MSc
  • Identifier: http://hdl.handle.net/10962/165755 , vital:41278
  • Description: The Onder Karoo fossil locality near Sutherland, Northern Cape, recently yielded an unprecedented diversity of middle Permian insects, which were preserved in deposits of an aquatic lake margin system, in the Lowermost Abrahamskraal Formation. A large number of Plecoptera (stonefly) specimens were found, and this study represents an in-depth analysis of these species in the context of plecopteran evolution. A significant contribution to current knowledge of the Plecoptera from the middle Permian to the present has been made, utilizing a combination of fossil and phylogenetic evidence to better understand the origins, evolution, diversity and biogeography of the stoneflies. Three new plecopteran species have been described from the Onder Karoo locality, which is recognized here as the first Lagerstätte of its kind in Gondwana. Possible ecological links and relationships with the plecopterans described here have been suggested, using extant Plecoptera as analogues. An in-depth, fossilcalibrated, dated phylogeny of the Plecoptera was completed, using representatives from all three dominant lineages, the Antarctoperlaria, Systellognatha and the Euholognatha. This provides strong support for the monophyly of the Notonemouridae and the Antarctoperlaria, however the monophyly of Systellognatha and Euholognatha was not supported. The Notonemouridae were found to represent an earlier divergence than previously believed, forming a sister group to the remaining Plecoptera. Through a combination of fossil and molecular evidence, strong support was found for the current distribution of the Plecoptera worldwide being attributable to vicariance caused by the rifting of Pangea, and subsequently Gondwana and Laurasia, and long range dispersal. The focussed effort to include Southern Hemisphere stoneflies throughout this study has been a valuable step in reducing the Northern Hemisphere bias which currently dominates plecopteran research and has assisted in opening the way for future research into this important group on a global scale.
  • Full Text:

The precarious ‘good mother’ position: a psychosocial reading of maternal subjectivity of working mothers in scarcely-resourced South African communities

  • Authors: Kinahan-Sweeney, Siobhan
  • Date: 2020
  • Subjects: Motherhood -- Psychological aspects -- South Africa , Working mothers -- South Africa -- Attitudes , Working mothers -- South Africa -- Psychology
  • Language: English
  • Type: text , Thesis , Doctoral , PhD
  • Identifier: http://hdl.handle.net/10962/142464 , vital:38082
  • Description: This psychosocial study investigates the maternal subjectivities of mothers returning to work after maternity leave, who are living in scarcely-resourced Cape Town communities in South Africa. Engaging with interview texts and listening to mothers’ talk, I explore how and why maternal subjectivity is constructed discursively and defensively in our talk. This thesis claims that these particular mothers predominately employ instrumental mothering discourse. The traditional subject position of the intensive mother – which is typically assumed to be the ‘good mother’ – is not a position available to these mothers due to their social circumstances and working role. Subsequently, material provision, the baby’s thriving and surviving body, finding substitute carers and maternal preoccupation are constructed as qualities of ‘good mothering’ in their talk. This ‘good mother’ position, however, is a precarious position that both these mothers and I invest in to defend against feelings towards their babies and themselves as well as to deny (maternal) ambivalence in a problematic social system. In a combined analysis drawing on discursive theory and psychoanalysis, more specifically contemporary attachment theory and intersubjectivity theory, I illustrate how both these mothers and I – as emotional, social and political subjects – co-construct maternal subjectivity. Based on the findings, recommendations for parent-infant interventions are discussed. Arguing that a purely psychoanalytic reading of investment perpetuates notions of individual blame and pathology, I advocate for a psychosocial reading that does not neglect failing social systems but rather pursues an open and reflective, yet critical, mindfulness when listening to talk.
  • Full Text:

Combining DNA barcoding and morphology to identify larval fishes from the nearshore environment off the south-east coast of South Africa

  • Authors: Somana, Zinzi Sinazo
  • Date: 2020
  • Subjects: Fishes -- Larvae -- South Africa -- Identification , Fishes -- Genetics -- Research -- Technique , Fishes -- South Africa -- Classification , Genetic markers
  • Language: English
  • Type: text , Thesis , Masters , MSc
  • Identifier: http://hdl.handle.net/10962/144605 , vital:38362
  • Description: The early life history stages of most marine fish species are undescribed. The problem is, most of these fishes have pelagic larvae which are minute, delicate forms. Linking the larval stage to an adult counterpart is extremely challenging as larvae are morphologically different from the adults. Historically, larval fish identification relied solely on distinguishing morphological characteristics and meristic measurements, which has resulted in taxonomic confusion and misidentification. The introduction of the deoxyribonucleic acid (DNA) barcoding technique as an alternative approach has been successful in positively identifying larval fishes. The correct identification of larval specimens is the key to a better understanding of larval ecology, which underpins the success of any adult fish population. This study aimed to positively identify larval fishes of the south-east coast of South Africa using morphological characteristics and DNA barcoding. Larval and eggs specimens for this study were collected from the shallow nearshore waters of the south-east coast of South Africa. A total of 177 larval specimens were used for morphological analysis. Body shape, gut shape, pigmentation and morphometric measurements (such as body depth, preanal length and total body length) were used to identify each specimen to the family level. In addition, a fragment of mitochondrial cytochrome c oxidase subunit 1 gene (COI) was adopted for sequencing to identify larval fish specimens and fish eggs. Sequences generated from this study were compared to those in the Barcode of Life Database (BOLD). When there were no close matches to a sequence, the GenBank nucleic acid sequence database, maintained by the National Center for Biotechnology Information (NCBI), was used as an alternative. A total of 18 different families were identified through morphology. Seventy-seven of the 177 larval specimens were not subjected to morphological identification due to physical damage. The majority of larvae identified using morphological characteristics belonged to either the Sparidae, Tripterygiidae or Gobiesocidae fish families. Through DNA barcoding, 12 fish families, 16 genera and 18 different species were identified. Ten DNA barcodes (categorised as ‘no match’) from 10 different larval specimens were not identified through any of the online databases. Therefore, the 2% threshold value was used to identify members of the same species. The K2P genetic distance relationships were calculated among the no match sequences and downloaded probability matches from NCBI. This resulted in two unknown specimens assigned to the Blenniidae and Gobiidae. All other taxa were identified to species level, except specimens representing the Gobiidae and Tripterygiidae families. Based on the K2P genetic distances Gobiidae representatives were categorised as members of the Caffrogobius genus. Twenty-eight barcodes represented specimens from the Tripterygiidae. DNA barcode data from COI was analysed using the standard phylogenetic procedures in MEGA6 to examine relationships and differentiation among sequences. These could not be identified to the lowest taxonomic rank due to limited sequence data to compare them with. The sequence data from these specimens gave different results in the two online databases. BOLD results were to family level (Tripterygiidae) and NCBI to the species level (Clinidae: Pavoclinus profundus). Results in this study confirmed the efficiency of the DNA barcoding technique in species level identification of fish larvae. The evidence from genetic barcodes of the Tripterygiidae specimens, supported by morphological characteristics, suggests the need for thorough research to identify the individuals to the species level. The fact that this study identified taxonomically problematic Gobiidae and Tripterygiidae specimens suggests that studies similar to this may highlight additional diversity and help to resolve the taxonomy of other species in these families. However, the lack of reference sequence data from the adult specimens, and especially those with cryptic diversity, were both shortcomings for the positive identification of larvae. With that being said, it shows the necessity for more research to be conducted on barcoding of larvae in general as to accommodate all kinds of species from biodiversity to economic perspectives.
  • Full Text:

A tribute to you

A holistic approach in understanding the effects of dietary protein sources on the growth and reproductive development of farmed abalone, Haliotis midae

  • Authors: Wu, Yu
  • Date: 2020
  • Subjects: Abalones -- Nutrition , Abalones -- Reproduction , Abalones -- Growth , Abalone culture , Haliotis midae -- Nutrition , Haliotis midae -- Reproduction , Haliotis midae -- Growth , Haliotis midae fisheries
  • Language: English
  • Type: text , Thesis , Doctoral , PhD
  • Identifier: http://hdl.handle.net/10962/167719 , vital:41506
  • Description: The combination of fishmeal and soya in the formulated feed of farmed South African abalone, Haliotis midae, not only improved abalone growth, but also the sustainability of the compound diets by reducing the reliance on fishmeal. However, the presence of soya produced larger gonads compared to those of abalone fed kelp or single-source protein diets. There is an increasing drive to control sexual maturation and reduce undesirable spawning events in farmed abalone. However, the reasons for the reported effects of soya inclusion on the reproductive development of farmed H. midae remain unresolved. The aim of this research was to use a combination of techniques to contribute to the understanding of the relationship between growth, reproductive and nutritional physiology of farmed H. midae fed diets of varying protein sources. These techniques included stable isotope analysis (SIA), fatty acid analysis, gonad histological assessments and haemolymph sexsteroid hormone analysis. The objectives were to examine the allocation of protein and nutritional components to somatic and reproductive tissues. This study also included the first attempt to investigate the role that sex steroid hormones play during gametogenesis. Abalone (40 – 50 g abalone-1) were fed one of four diets: either a single-source protein-based diet, i.e., (1) fishmeal-only (FM) or (2) soya-only (S), or a combination diet of (3) fishmeal-soya (FM S) or (4) fishmeal-sunflower meal (FM SM). Sampling occurred in 45-day intervals over one year. Dietary protein source had an effect on the growth of abalone, with enhancements in growth linked to the combination of fishmeal and a plant-protein source. The fishmeal ingredient was the most utilised protein source throughout the temporal changes in protein allocation into somatic and reproductive tissue, followed by soya and then sunflower meal. The mean whole- body mass of abalone was significantly influenced by an interaction between time and dietary treatment, with average whole-body mass changing differently over time between treatments (RM-ANOVA, F(24, 96) = 2.13, p = 0.005). Overall, abalone that were fed FM S had higher mean whole-body mass values than abalone that were fed the single-protein based diets, while abalone that were fed FM SM were similar to animals from all dietary treatments (RMANOVA, F(3, 12) = 5.75, p = 0.01). Male abalone had significantly higher gonad bulk index (GBI) values compared to females (RM-ANOVA, F(1, 24) = 49.03, p < 0.001) and this was independent of dietary treatment. Within each sex, female abalone fed the FM S diet (15.92 ± 1.88 mm3 g-1) had significantly higher GBI values than abalone fed S (9.76 ± 1.08 mm3 g-1), while abalone fed FM (11.96 ± 1.71 mm3 g-1) and FM SM (11.90 ± 0.80 mm3 g-1) were similar to abalone from all other dietary treatments (Tukey’s HSD, p < 0.05). Male abalone fed the FM S (21.59 ± 2.10 mm3 g-1) and FM SM diet (19.30 ± 2.63 mm3 g-1) had similar GBI values and they were significantly higher than in abalone fed the S diet (14.74 ± 1.27 mm3 g-1), while abalone fed FM S had significantly higher GBI values than abalone that consumed the FM diet (15.08 ±1.63mm3 g-1) ( Tukey’s HSD, p < 0.05). Although sunflower meal was poorly utilised, it produced similar overall growth to abalone that were fed the FM S diets. Yet, feed conversion ratio values were significantly lower for abalone fed FM S (1.30 ± 0.13) compared to those in the other three treatments, with ratios ranging from 1.65 – 1.72 over the one-year. The fatty acid compositions of the somatic and gonadal tissues were similar between treatments (PERMANOVA, p = 0.21), while fatty acid composition was influenced by sampling day, tissue type and abalone sex (PERMANOVA, p < 0.05). The essential fatty acids (EFAs) eicosadienoic acid and a-linolenic acid were present in abalone tissue, but they were not detected in the diets, suggesting the important role that an alternate food source (e.g. farmed abalone also had access to diatoms) may have played and the ability that H. midae may have in converting long-chain polyunsaturated fatty acids from C18 precursors. A change in the abundance of EFAs in the gonad tissue during highest and lowest GBI values suggested that arachidonic, eicosapentaenoic, g-linolenic and linoleic acid were important in females, while eicosapentaenoic, eicosadienoic and a-linolenic acid were important for male reproductive development. Dietary protein sources had an effect on the frequency distribution of maturity stages, where females that were fed FM S produced more ripe gonads and more males that were fed FM SM contained testes that showed signs of ripeness over the one-year study. Although dietary protein influenced the sex steroid concentrations in females and males, exhibiting fluctuations throughout the one-year period, no distinct pattern linked to gametogenesis were observed. The results from this study illustrate: (1) the importance of conducting laboratory studies when implementing SIA and mixing models in aquaculture nutrition; (2) conducting nutritional studies on mature, grow-out abalone; and (3) assessing the importance of naturally occurring diatoms in their diet and their contribution to growth and reproduction. The novel contribution of this research towards abalone nutritional physiology, the implications of these findings to industry as well as potential considerations for future studies were addressed.
  • Full Text:

The role of flexible working in achieving a work-life balance: a case study of information technology consultants of Kestrel Business Solutions – London, United Kingdom

  • Authors: Nyamujara, Tinashe
  • Date: 2020
  • Subjects: Kestrel Business Solutions , Flexible work arrangement -- Case studies , Work-life balance , Flexitime , Telecommunting , Telecommunting -- Case studies
  • Language: English
  • Type: text , Thesis , Masters , MBA
  • Identifier: http://hdl.handle.net/10962/167245 , vital:41459
  • Description: This research was a Case Study on the role of Flexible Working in achieving a Work – Life Balance, based on the Information Technology Consultants of Kestrel Business Solutions – a company based in London, the United Kingdom. The study set out to determine what aspects of flexible working can reduce work - related stress; home - related stress; improve personal wellbeing; identify the pitfalls of flexible working, and to recommend mitigating actions. The literature review identified five different, but complimentary theories that included: The Spill over Theory; Balanced Theory; Resource Based Theory; Compensation Theory and the Wellness Theory to unpack and explore the concept of Work - Life Balance. The study followed a predominantly qualitative methodology approach and used thematic analysis to identify key ideas from the data. Interviews and questionnaires were used to obtain data from the respondents, in addition to being a data triangulation exercise. From a population of 10 subjects - purposeful sampling was used to select a sample of 10 respondents - made up of 3 males and 7 females. All respondents were employees of Kestrel Business Solutions. 6 respondents were interviewed and given questionnaires to fill out. 6 face to face interviews were conducted, and 6 questionnaires completed until saturation was achieved - indicating a survey response rate of 100%. The results from the data collection generally showed how aspects of flexible working like telecommuting, flexitime and homeworking ultimately helped the employees to achieve a Work-Life Balance - by primarily influencing how they balanced their work, home, and personal commitments. Importantly, the study also identified pitfalls of flexible working; like employees feeling isolated and the pressure to perform. Potential mitigating efforts identified in the study included, providing more company support and education for flexible working initiatives. The study concluded by acknowledging the limitations of the study, which included time constraints and the small population, and sample size of the study. In its conclusion, the study identified recommendations for future studies like: increasing the population and sample size, and devoting more time to the study, for more generalized and conclusive findings.
  • Full Text:

Impacts of a trophy hunting ban on private land conservation in South African biodiversity hotspots:

  • Authors: Parker, Kim , de Vos, Alta , Clements, Hayley S , Biggs, Duan , Biggs, Reinette
  • Date: 2020
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/158219 , vital:40163 , https://0-doi.org.wam.seals.ac.za/10.1111/csp2.214
  • Description: Private land conservation areas (PLCAs) have become critical for achieving global conservation goals, but we lack understanding of how and when these areas respond to global pressures and opportunities. In southern Africa, where many PLCAs rely on trophy hunting as an income‐generating strategy, a potential ban on trophy hunting locally or abroad holds unknown consequences for the future conservation of these lands. In this study, we investigate the consequences of a potential trophy hunting ban in PLCAs in two biodiversity hotspots in South Africa's Eastern and Western Cape provinces. We used semistructured interviews with PLCA managers and owners to elicit perceived impacts of an internationally imposed trophy hunting ban on conservation activities in PLCAs, and to probe alternative viable land uses.
  • Full Text:

Hope in a small town

  • Authors: Ngubelanga, Xolisa
  • Date: 2020
  • Subjects: South African fiction (English) -- 21st century , South African fiction (English) -- History and criticism , Short stories, South African (English) -- 21st century
  • Language: English
  • Type: text , Thesis , Masters , MA
  • Identifier: http://hdl.handle.net/10962/145089 , vital:38407
  • Description: Writing has always experienced as the elite relative in the family of arts, especially among African artists and art consumers. Somehow writing has in past and to a great extent still is in the present been referred more than song, storytelling and dancing. Interrogating the past of colonization of African narratives I could point that this is the case because African expression had always packaged in a ‘come see the Africans are dancing, singing or storytelling. Listen to their clicks.’ Writing, however, could only be executed by those Africans of white assimilation with higher social status and missionary education. Among amaXhosa, the disparity of socially lesser African arts and that of the educated has been termed the narrative of Amaqaba and Amagqobhoka. Amaqaba being those whose stories have taken longer to be documented in modern means of writing but have been enriched through years of live telling. Amagqobhoka on the other hand who easily documented their narrative after having been trained in writing have enjoined the audience of readers and access into literary space longer.
  • Full Text:

The impact of minimum wages on human resource management practices in the hospitality industry: a case study of selected firms in Polokwane, Limpopo Province

Formulation and evaluation of liposomal films for buccal delivery of antiretroviral drug

  • Authors: Okafor, Nnamdi Ikemefuna
  • Date: 2020
  • Subjects: Liposomes , Highly active antiretroviral therapy , Antiretroviral agents , HIV infections -- Prevention
  • Language: English
  • Type: text , Thesis , Masters , MSc
  • Identifier: http://hdl.handle.net/10962/117161 , vital:34485
  • Description: The human immune deficiency virus (HIV) infection has been ranked as one of the most devastating microbial infections in the world. This status is a result of the HIV rapid genetic variation, which limits discovery of a vaccine. Use application of antiretroviral therapy (ARVT) in treatment of the disease caused by the HIV infection (known as acquired immunodeficiency syndrome, HIV-AIDS) is frequently compromised by several factors such as the low bioavailability and severe adverse effects associated with the existing antiretroviral drugs (ARVDs). This underlines the need for controlling the pharmacokinetics profiles of ARVD using effective vehicles that can modify drug biodistribution. The same is true for many other conditions, where delivery systems can determine the success or failure of treatment by controlling pharmacokinetic and dynamic properties. The mucosal linings of the oral cavities in addition offer adorable route of administration for systematic drug delivery, improving drug therapeutic performance and often preferred by clinicians and patients. Liposomes are tiny spherical sacs of phospholipid molecules enclosing water droplets, formed (artificially) to carry drugs or other substances into the tissues by crossing and targeting to specific organelles. This work therefore focused on preparation of liposomes and liposomal buccal films (BFs) for potential buccal delivery of efavirenz, an ARVD model endowed with poor solubility and several side effects. The liposomes were prepared by thin film hydration method using crude soybean lecithin (CL) and cholesterol. Efavirenz loaded liposomes were evaluated for particle size, Zeta potential (ZP), morphology, encapsulation efficiency (EE%) and release kinetics studies. The physiochemical properties of the liposomes were also evaluated using Differential Scanning Calorimetry (DSC), X-ray diffraction (XRD), energy dispersity spectroscopy (EDS), and Fourier transform infrared (FTIR), while the formulation with the best encapsulation efficiency was used as the solvent medium for the buccal film formation. The buccal films were prepared using solvent casting method, where the liposomal suspension was used as the dispersing medium. The films were optimized for physical properties (thickness, weight variation and folding endurance) using digital Vernier calliper and digital weighing balance. The physiochemical properties of the selected BFs films made of Carbopol (CP) and its combination with Pluronic F127 (PF127) were further characterized using XRD, DSC, FTIR, Transmission Electron Microscopy (TEM), EDS and Scanning Electron Microscopy (SEM). The permeation study of the selected BFs was investigated using Franz diffusion cell. The BFs composed of CP alone or its combination with PF127 demonstrated much better bio-adhesive properties than the films made of other polymers (like Hydroxyl propyl methyl cellulose, HPMC) alone or in combination with PF127. The developed liposome formulation showed high encapsulation 98.8 ± 0.01 % in CL to cholesterol mass ratio of 1:1 and total lipid to drug mass ratio of 2:1. The average particle size 104.82 ± 2.29 nm and Zeta potential -50.33 ± 0.95 mV of these liposomes were found to be attractive for targeted delivery to the HIV infected cells. The CP based BFs (without and with PF127) exhibited good film thickness 0.88 ± 0.10 and 0.76 ± 0.14 mm, with weight uniformity 68.22 ± 1.04 and 86.28 ± 2. 16 mg, satisfactory flexibility values 258 and 321, and slightly acidic pH 6.43 ± 0.76 and 6.32 ± 0.01. The swelling percentage was found to be 50 % for CP film alone and 78 % for CP film with PF127. The cumulative amount of drug that permeated through the buccal epithelium over 24 hours was about 66 % from CP film alone and 75 % from CP film with PF127. Since no evidence of the liposomal encapsulation of EFV have been reported to our knowledge, we find the insights from the present study valuable as a set of preliminary data to encourage further investigations of the encapsulation and delivery of EFV like antiretrovirals for enhanced solubility, site targeting and prolonged release using crude soybean lecithin and mucoadhesive polymers, which holds some added economical values as naturally occurring lipid and polymeric mixtures as a promising delivery systems for buccal delivery of ARVDs.
  • Full Text:

Social media and brand image: a longitudinal study of Eastern Cape universities

  • Authors: Mnqeta, Lusanda
  • Date: 2020
  • Subjects: Multivariate analysis -- Graphic methods , Branding (Marketing) -- South Africa , Chernoff faces , Social media -- South Africa , Universities and colleges -- South Africa -- Marketing , Universities and colleges -- South Africa -- Marketing -- Case studies
  • Language: English
  • Type: text , Thesis , Masters , MBA
  • Identifier: http://hdl.handle.net/10962/143959 , vital:38298
  • Description: It is important for Higher Education Institutions to have marketing strategies that focus on understanding the customer needs in the 21st century. The rapid growth of the internet and the Web 2.0 have led individuals and organisations into applying social media as a branding and communication tool. Hence this study focused on comparing the influence of social media on four Eastern Cape universities in relation to social media metrics and visually demonstrated through the computer-generated human face, the Chernoff faces. Using diary and literature study, the study adopted a case study research design. The researcher sampled four universities using a purposeful sampling technique. Chernoff faces were used to enhance the ability of the reader to immediately understand significant occurrences based on social media metric indicators. To demonstrate multivariate data, the faces brought an original method of expressing complex data as opposed to traditional methods. The study found that Brand management and Resource-Based Theory (RBT) plays a pivotal role in social media marketing as this can lead to organisations having a competitive advantage. The study recommended that strategies to utilise social media as a resource should be put in place to lead to competitive advantage, as suggested by the Resource-based theory. The study concluded that various social media factors can influence the brand image of universities, positively (going to buy) and negatively (never going to buy). Both positive and negative purchase intent are found to be an influential indicator on the brand as they are affected by customer satisfaction.
  • Full Text:

A critical analysis of social enterprise in Slovenia

  • Authors: Malila, Brett
  • Date: 2020
  • Subjects: Social entrepreneurship -- Slovenia , Social entrepreneurship -- Slovenia -- Case studies , Social entrepreneurship -- Law and legilstion-- Slovenia , Business enterprises -- Law and legilstion-- Slovenia
  • Language: English
  • Type: text , Thesis , Masters , MBA
  • Identifier: http://hdl.handle.net/10962/166436 , vital:41364
  • Description: This research presents a case study on the nature of social enterprise in Slovenia. From a resource-based view (RBV), the case study has been used to show what some of the intangible resources are that can be used to promote sustainable social enterprise (SE). The purpose of this research study is to analyse social enterprises in Slovenia in order to establish a framework which other social entrepreneurs can use as the basis from which to operate and achieve competitive advantage. It is an important piece of research for both the process of social enterprise development in Slovenia, as well as to provide ideas and thoughts as to the way forward in this sector for other developing societies. Social enterprise is a developing field and it has been be important to develop cases to begin to explore the concept with real life actualities. The goal is to provide a clearer conceptualisation from which other social entrepreneurs can use as the basis to analyse, plan and improve social enterprise in their own specific contexts. The primary purpose of the study is thus to unpack the core elements that identify social enterprise in Slovenia using the resource-based view. The research aims to understand social enterprise within Slovenia in relation to where it occurs, which are the main industries concerned, and what are the unique resources used to promote sustainable growth. To achieve this, the research was guided by the resource-based view for social enterprise as highlighted by Day and Jean-Denis (2016) as well as that proposed by Bacq and Eddleston (2018). A mind map for a possible route towards improved implementation and understanding of social enterprise in Slovenia, was done through accessing registered social enterprises. This database was from the Ministry of Economic Development in Slovenia. An analysis of 2591 social enterprise, a desktop review of the Slovenian legislation on social enterprise and the unpacking of unique resources available to Slovenian social enterprise was done. This provided a perfect test case to show how the provision of legislation, supportive structures; financial targets, a regional vision and government mentoring social enterprise enhance a contested terrain in Slovenia. Findings highlighted that there have been sustainable successes, but not at the levels expected. It is clear that the government has created various unique resources to build and develop the social enterprise (SE) sector. From an RBV analysis of the social enterprise environment in Slovenia, it is essential to have resources such as legislation, mind-set, in migration (labour) and youth skills be created, monitored and supported. However, there is a need for improved monitoring and tighter implementation of the legislation for social enterprise to provide the solution to destructive social ills.
  • Full Text:

Symmetry and asymmetry in electrocatalysis: enhancing the electrocatalytic activity of phthalocyanines through synergy with doped graphene quantum dots

  • Authors: Nkhahle, Reitumetse Precious
  • Date: 2020
  • Subjects: Phthalocyanines , Quantum dots , Graphene
  • Language: English
  • Type: text , Thesis , Masters , MSc
  • Identifier: http://hdl.handle.net/10962/117585 , vital:34529
  • Description: An exploration on the enhancement of the electrocatalytic activity of phthalocyanines (Pcs) through coupling with a series of graphene quantum dots (GQDs) is undertaken. The preliminary studies using symmetrical Pcs, a cobalt and an iron chloride tetra substituted diethylaminophenoxy Pc (complexes 1 and 2), for the electro-oxidation of nitrite revealed through the various sequential modifications that doped GQDs fare better than their pristine counterparts with respect to improving the electrocatalytic behaviour of Pcs, in particular, the nitrogen-doped GQDs (NGQDs). Following up on this, a series of asymmetric Pc complexes; 2,9,16-tris-(4-tert-butylphenoxy) mono carboxyphenoxy phthalocyanato cobalt (II) (3), 2,9,16-tris-(4-tert-butylphenoxy) mono aminophenoxy phthalocyanato cobalt (II) (4), 2,9,16-tris-(3-diethylamino)phenoxy) mono carboxyphenoxy phthalocyanato cobalt (II) (5) and 2,9,16-tris-(3-diethylamino)phenoxy) mono aminophenoxy phthalocyanato cobalt (II) (6) was prepared in which push-pull systems were compared to other asymmetric complexes that lack this effect towards the electrocatalytic sensing of hydrazine. All asymmetric complexes (3-6) were π-stacked to the NGQDs while those with an NH2 group (4 and 6), were also covalently linked to the NGQDs. These complexes and their corresponding conjugates were characterized accordingly and applied as electrocatalysts in the oxidation of hydrazine. The electrochemical studies revealed that π π stacking yields better responses (higher sensitivities and lower limits of detection) than covalent linking because there are less forces acting on the graphene network. Covalent linking introduces both tensile and compressive forces which in turn results in an increase in the ID/IG ratio and that is unfavourable for electrocatalysis. In comparing the electrodes composed of the π-stacked conjugates to those altered through sequential modifications, despite the conditions not being the same, it can be inferred that the magnitude of the electrostatic forces between the Pcs and the GQDs also plays a significant role in electrocatalysis. The π-stacked conjugates, owing to the manner in which they were prepared, have stronger electrostatic forces acting between the Pc and GQDs hence they were able to elicit a better electrochemical response than the sequentially modified electrodes. In addition to that, it appears that asymmetric Pcs are better electrocatalysts in comparison to the symmetric Pcs.
  • Full Text:

Towards a capability maturity model for a cyber range

  • Authors: Aschmann, Michael Joseph
  • Date: 2020
  • Subjects: Computer software -- Development , Computer security
  • Language: English
  • Type: text , Thesis , Masters , MSc
  • Identifier: http://hdl.handle.net/10962/163142 , vital:41013
  • Description: This work describes research undertaken towards the development of a Capability Maturity Model (CMM) for Cyber Ranges (CRs) focused on cyber security. Global cyber security needs are on the rise, and the need for attribution within the cyber domain is of particular concern. This has prompted major efforts to enhance cyber capabilities within organisations to increase their total cyber resilience posture. These efforts include, but are not limited to, the testing of computational devices, networks, and applications, and cyber skills training focused on prevention, detection and cyber attack response. A cyber range allows for the testing of the computational environment. By developing cyber events within a confined virtual or sand-boxed cyber environment, a cyber range can prepare the next generation of cyber security specialists to handle a variety of potential cyber attacks. Cyber ranges have different purposes, each designed to fulfil a different computational testing and cyber training goal; consequently, cyber ranges can vary greatly in the level of variety, capability, maturity and complexity. As cyber ranges proliferate and become more and more valued as tools for cyber security, a method to classify or rate them becomes essential. Yet while a universal criteria for measuring cyber ranges in terms of their capability maturity levels becomes more critical, there are currently very limited resources for researchers aiming to perform this kind of work. For this reason, this work proposes and describes a CMM, designed to give organisations the ability to benchmark the capability maturity of a given cyber range. This research adopted a synthesised approach to the development of a CMM, grounded in prior research and focused on the production of a conceptual model that provides a useful level of abstraction. In order to achieve this goal, the core capability elements of a cyber range are defined with their relative importance, allowing for the development of a proposed classification cyber range levels. An analysis of data gathered during the course of an expert review, together with other research, further supported the development of the conceptual model. In the context of cyber range capability, classification will include the ability of the cyber range to perform its functions optimally with different core capability elements, focusing on the Measurement of Capability (MoC) with its elements, namely effect, performance and threat ability. Cyber range maturity can evolve over time and can be defined through the Measurement of Maturity (MoM) with its elements, namely people, processes, technology. The combination of these measurements utilising the CMM for a CR determines the capability maturity level of a CR. The primary outcome of this research is the proposed level-based CMM framework for a cyber range, developed using adopted and synthesised CMMs, the analysis of an expert review, and the mapping of the results.
  • Full Text:

Nonlinear optical response and electrocatalytic activity of cobalt phthalocyanine clicked zinc oxide nanoparticles

  • Authors: Mpeta, Lekhetho S , Sekhosana, Kutloano E , Nyokong, Tebello
  • Date: 2020
  • Subjects: To be catalogued
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/186179 , vital:44471 , xlink:href="https://doi.org/10.1016/j.ica.2020.119661"
  • Description: In this article, we report on the linking of cobalt tetrakis (4-pentyn-oxy) phthalocyanine (CoTPPc) to ZnO nanoparticles via click chemistry. Subsequently, electrocatalytic activity and nonlinear optical properties were investigated (the latter using an open Z-scan technique at 532 nm). The linking of CoTPPc with ZnO resulted in the lowest limiting intensity value of 0.27 J.Cm−2, the βeff (cmW−1) values were found to be 1.51 × 10-8 and 7.10 × 104 for ZnO and CoTPPc-ZnO respectively. The catalytic rate constants (M−1s−1) (and limits of detection) were 4.1 × 104 (12.87 µM), 5.7 × 104 (8.62 µM) and 7.36 × 104 (4.35 µM) for ZnO, CoTPPc and CoTPPc-ZnO. Hence linking ZnO nanoparticles to CoTPPc result in the enhancement of both nonlinear optical behaviour and catalytic activity.
  • Full Text:

Enhanced Light-Driven Antimicrobial Activity of Cationic Poly (oxanorbornene) s by Phthalocyanine Incorporation into Polymer as Pendants

  • Authors: Ahmetali, Erem , Sen, Pinar , Süer, N Ceren , Aksu, Burak , Nyokong, Tebello , Eren, Tarik , Sener, Kasim M
  • Date: 2020
  • Subjects: To be catalogued
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/185976 , vital:44453 , xlink:href=" https://doi.org/10.1002/macp.202000386"
  • Description: Amphiphilic poly(oxanorbornene)s are promising synthetic polymers that mimic the structural properties and antimicrobial functions of naturally occurring antimicrobial peptides. Here, poly(oxanorbornene)s bearing pendant zinc(II) phthalocyanine and triphenyl(ethyl) phosphonium functionalities are synthesized by ring-opening metathesis polymerization (ROMP). Fluorescence, singlet oxygen and triplet quantum yields of polymers are measured in dimethyl sulfoxide and aqueous medium. The singlet oxygen quantum yields of copolymers with the highest triphenyl and triethyl phosphonium content are found to be 0.29 and 0.41, respectively. Then, antimicrobial activities of polymers against Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus) are investigated under both dark and light conditions. Synergistic effect of zinc(II) phthalocyanine and phosphonium-containing poly(oxanorbornene) is observed that the conjugate possessing the most triphenyl phosphonium side chains has the highest activity under light against both gram-positive and gram-negative bacterial strains after 80 min irradiation, reducing the survival of E. coli or S. aureus by 99.9999%. Hemolytic concentrations of the copolymers are found between 8 and 512 µg mL−1. Scanning electron microscopy (SEM) proves that the bacteria membrane deforms after contacting with the biocidal polymer.
  • Full Text:

STIP1/HOP regulates the actin cytoskeleton through interactions with actin and changes in actin-binding proteins cofilin and profilin:

  • Authors: Beckley, Samantha Joy , Hunter, Morgan C , Kituyi, Sarah N , Wingate, Ianthe , Chakraborty, Abantika , Schwarz, Kelly , Makhubu, Matodzi P , Rousseau, Robert P , Ruck, Duncan K , de la Mare, Jo-Anne , Blatch, Gregory L , Edkins, Adrienne L
  • Date: 2020
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/165373 , vital:41238 , https://doi.org/10.3390/ijms21093152
  • Description: Cell migration plays a vital role in both health and disease. It is driven by reorganization of the actin cytoskeleton, which is regulated by actin-binding proteins cofilin and profilin. Stress-inducible phosphoprotein 1 (STIP1) is a well-described co-chaperone of the Hsp90 chaperone system, and our findings identify a potential regulatory role of STIP1 in actin dynamics. We show that STIP1 can be isolated in complex with actin and Hsp90 from HEK293T cells and directly interacts with actin in vitro via the C-terminal TPR2AB-DP2 domain of STIP1, potentially due to a region spanning two putative actin-binding motifs. We found that STIP1 could stimulate the in vitro ATPase activity of actin, suggesting a potential role in the modulation of F-actin formation. Interestingly, while STIP1 depletion in HEK293T cells had no major effect on total actin levels, it led to increased nuclear accumulation of actin, disorganization of F-actin structures, and an increase and decrease in cofilin and profilin levels, respectively. This study suggests that STIP1 regulates the cytoskeleton by interacting with actin, or via regulating the ratio of proteins known to affect actin dynamics.
  • Full Text:

A comparative analysis of social media brand image of insurance companies in South Africa: a longitudinal study

  • Authors: Gudu, Daniel
  • Date: 2020
  • Subjects: Social media -- South Africa , Internet marketing -- South Africa , Chernoff faces , Ínsurance companies -- South Africa -- Marketing , Insurance companies -- South Africa -- Case studies , Multivariate analysis -- Graphic methods
  • Language: English
  • Type: text , Thesis , Masters , MBA
  • Identifier: http://hdl.handle.net/10962/144277 , vital:38327
  • Description: Social media is changing the way business is conducted. Almost five billion videos are watched on YouTube every single day. Social media has an extensive worldwide presence. Out of the total global population of over 7,5 billion people, over 4 billion are internet users. Of these, over 3 billion are active on social media. Social media is very influential in today's decision-making processes. Businesses must integrate social media into their strategies. The purpose of this research was to investigate the use of a novel method, Chernoff Faces, to assess and compare the social media brand images of six insurance companies in South Africa based on social conversation measurement. The intention of research was towards observing existing situations at hand and pointing out the game changers that can provide the industry with a new leap. Social media are multidimensional and understanding them requires tracking different measures simultaneously. Integrating social media into a communication strategy leads to a problem in finding the best way to portray and communicate multivariate data. It is essential to find the best way to represent and transmit the data so that marketing executives can quickly and easily monitor changes in brand images. Previous studies have successfully proved the possibility of using this method to gauge a "snapshot in time." This study took the concept further by closely monitoring the results for a set of brands over a period to account for the dynamic nature of social media. Accordingly, the study was a longitudinal study of 30 days. Data on the insurance companies was collected from Social Mention, a social media search and analysis platform that aggregates user-generated content into a single stream of information. A tool in the statistical software Stata, Chernoff's faces, was used to analyse the results by generating facial expressions to the metrics associated with the social mentions of each of the insurance companies. The resulting facial expressions were then analysed to recognise the more favourable and stable brands and those that need appropriate risk management. Managing Social Media is challenging as managers must always keep it as positive as possible. Brand managers, therefore, need a better tool to gauge the mood in social media conversations due to the fast-changing nature of social media and the importance of social media to business especially insurance.
  • Full Text:

Guidelines for the user interface design of electronic medical records in optometry

  • Authors: Nathoo, Dina
  • Date: 2020
  • Subjects: User interfaces (Computer systems) , Medical records -- Data processing , Optometry -- South Africa -- Eastern Cape , System design , Workflow management systems
  • Language: English
  • Type: Thesis , Masters , MCom
  • Identifier: http://hdl.handle.net/10962/148782 , vital:38773
  • Description: With the prevalence of digitalisation in the medical industry, e-health systems have largely replaced the traditional paper-based recording methods. At the centre of these e-health systems are Electronic Health Records (EHRs) and Electronic Medical Records (EMRs), whose benefits significantly improve physician workflows. However, provision for user interface designs (UIDs) of these systems have been so poor that they have severely hindered physician usability, disrupted their workflows and risked patient safety. UID and usability guidelines have been provided, but have been very high level and general, mostly suitable for EHRs (which are used in general practices and hospitals). These guidelines have thus been ineffective in applicability for EMRs, which are typically used in niche medical environments. Within the niche field of Optometry, physicians experience disrupted workflows as a result of poor EMR UID and usability, of which EMR guidelines to improve these challenges are scarce. Hence, the need for this research arose, aiming to create UID guidelines for EMRs in Optometry, which will help improve the usability of the optometrists’ EMR. The main research question was successfully answered to produce the set of UID Guidelines for EMRs in Optometry, which includes guidelines built upon from literature and made contextually relevant, as well as some new additions, which are more patient focused. Design Science Research (DSR) was chosen as a suitable approach, and the phased Design Science Research Process Model (DSRPM) was used to guide this research. A literature review was conducted, including EHR and EMR, usability, UIDs, Optometry, related fields, and studies previously conducted to provide guidelines, frameworks and models. The review also included studying usability problems reported on the systems and the methods to overcome them. Task Analysis (TA) was used to observe and understand the optometrists’ workflows and their interactions with their EMRs during patient appointments, also identifying EMR problem areas. To address these problems, Focus Groups (FGs) were used to brainstorm solutions in the form of EMR UID features that optometrists’ required to improve their usability. From the literature review, TAs and FGs, proposed guidelines were created. The created guidelines informed the UID of an EMR prototype, which was successfully demonstrated to optometrists during Usability Testing sessions for the evaluation. Surveys were also used for the evaluation. The results proved the guidelines were successful, and were usable, effective, efficient and of good quality. A revised, final set of guidelines was then presented. Future researchers and designers may benefit from the contributions made from this research, which are both theoretical and practical.
  • Full Text:

Investigating visual literacy development through advertisements: a case of Grade 7 English Language Teaching in Mount Frere District, Eastern Cape

  • Authors: Mbuqe, Zolile Patrick
  • Date: 2020
  • Subjects: Visual literacy , English language -- Study and teaching -- Audio-visual aids , Second language acquisition -- South Africa , English language -- Study and teaching -- Activity programs , Advertising -- Study and teaching , Visual learning , English language -- Study and teaching -- South Africa
  • Language: English
  • Type: text , Thesis , Masters , MEd
  • Identifier: http://hdl.handle.net/10962/143458 , vital:38248
  • Description: Although the Curriculum and Assessment Policy Statement lists visual literacy as one of the aspects of English First Additional Language in Grades 4-12, many teachers face challenges in teaching it. This study aimed to investigate visual literacy development through advertisements. Drawing on Cultural Historical Activity Theory, this qualitative intervention designed two research phases in which data was collected and analysed. The first phase, a pre-intervention, included lesson observation, analysis of documents and post-lesson semi-structured interviews. Based on Phase One findings and using advertisements as an entry point in developing visual literacy, Phase Two occurred at a change laboratory workshop and engaged eight teachers with the dynamics of meaning making and teaching. This data was analysed using elements of social semiotics and Serafini’s resource practices. The key findings are that despite low visual literacy understanding and practices, rigorous formative intervention indicated advancement in teachers’ understanding of visual literacy. In addition, through this intervention, teachers developed agency in dealing with schooling adversities such as lack of resources and knowledge hence further formative intervention research in visual literacy is recommended for both EFAL subject advisors and teachers.
  • Full Text:
  • Disclaimer
  • Privacy
  • Copyright
  • Contact