1834 research outputs found
Sort by
Identiteitskonfigurasies in wit Afrikaanse rap-musiek met spesifieke verwysing na Die Antwoord, Jack Parow en Bittereinder
No full textn hierdie studie word identiteitskonfigurasies in wit Afrikaanse rap-musiek ondersoek, met spesifieke verwysing na die rap-kunstenaars Die Antwoord, Jack Parow en Bittereinder. Rap is ’n wesenlike element van hip-hop, ’n kultuurvorm wat gedurende die 1970’s onder die sosiopolities en ekonomies gemarginaliseerde jeug in New York se Suid-Bronx ontwikkel het, maar wat ook ’n verbintenis het met swart mondelinge praktyke wat eeue terug strek. Sedert die ontstaan van hip-hop het rap daarmee saam aangehou om te evolueer en die wêreld oor te versprei, waar dit op verskeie plaaslike vlakke buite Noord-Amerika ingespan word as een van vele meganismes in die voortgaande prosesse van kultuurskepping en identiteits-konfigurasie. In hierdie sin is hip-hop ’n glokale kunsvorm, omdat dit ’n globale verskynsel is wat op plaaslike (lokale) vlak aangepas word om te voldoen aan plaaslike vereistes, waar dit dan ook ’n plaaslike karakter verkry. Hip-hop geniet wêreldwyd al hoe meer belangstelling in die akademie, maar waar dit aanvanklik ondersoek is as swart Amerikaanse kultuurvorm, het daar sedert die eeuwending ’n tendens ontwikkel om ook die onderskeie plaaslike permu-tasies van hip-hop op verskillende vastelande en in verskeie tale te ondersoek om meer te wete te kom van die rol wat dit in terme van die voortsetting van plaaslike mondelinge praktyke, en prosesse van kultuur- en identiteitskonfigurasies speel.
Populêre musiekvorme is een van verskeie ruimtes waarbinne die Suid-Afrikaanse jeug op aktiewe wyse voortdurend kwessies van identiteit ondersoek en konfigureer. In hierdie proefskrif word daar toegetree tot sowel die diskoers oor plaaslike populêre musiek en identiteit, as die diskoers oor die verskeie glokale permutasies van hip-hop deur die ontwikkeling en aard van wit Afrikaanse rap-musiek te ondersoek. Die studie sluit ook aan by plaaslike witheidstudies waar wit identiteit sedert demokratisering in 1994 toenemend onder die soeklens kom en op dié wyse word die sentrale magsposisie wat witheid weens die koloniale en apartheidsgeskiedenis beklee het, krities beskou en uitgedaag. Sodoende, en deur die ondersoek na wit kunstenaars wat op verskeie wyses ’n histories swart kultuurvorm inspan, word enige nosie van essensiële of vaste identiteite betwis.
’n Ondersoek na die hip-hop-kultuur en die mondelinge tradisies wat dit voorafgegaan het, word ingestel ten einde die simboliese kapitaal, aard en kenmerke van rap-musiek te identifiseer. Daar word ook gekyk na die eerste permutasies van hip-hop in Suid-Afrika gedurende die 1980’s en 1990’s. Drie gevallestudies volg daarop, naamlik van Die Antwoord, Jack Parow en Bittereinder. Deur op interdissiplinêre wyse te werk te gaan, word ’n kwalitatiewe ondersoek ingestel na die maniere waarop hierdie wit plaaslike rappers deur middel van die gebruik van ’n oorspronklike swart kultuurvorm met die kwessie van identiteit omgaan, inaggenome die unieke Suid-Afrikaanse konteks. Uiteindelik word daar getoon hoe hip-hop gebruik word in die immer ontwikkelende plaaslike prosesse van die kreolisering van taal en musiek deur taal en musiek.National Research Foundatio
Developing and testing a cost effective thermal rock bed storage system.
No full textIn the concentrating solar power industry, thermal energy storage is an attractive
solution for storing excess energy for the periods with insufficient solar resource. Energy storage in the form of sensible heat is a mature and practical method of storing energy for later use. Current thermal energy storage
technologies are expensive and alternative solutions are needed. The ultimate goal of a more cost effective thermal storage for concentrating solar power is to
decrease the levelized cost of electricity. Other than the potential for capital cost reduction, it is also adding value to concentrating solar power in industry compared to other renewable technologies. With thermal energy storage, a renewable energy electricity production plant can deliver electricity on demand and support the national grid. Thermal energy storage is a well-proven
concept that can meet the need for more cost effective alternatives.
The development of a novel cost effective thermal energy storage for air at 600° C with a unique system layout is covered in this project. This novel thermal energy storage concept has potential to reduce the specific installation
cost per kWh installed. A test facility was constructed in this project for testing the feasibility of a specific concept of a packed bed thermal energy storage.
The packed bed consist of a conical rock pile as a storage medium and air as the heat transfer fluid.
The test facility has a scalable design of a specific concept of a packed rock bed for thermal energy storage system. An inverted thermocline is implemented in this concept where the heat is stored at the bottom of the packed bed.
A cost effective layout is presented, with each component and subsystem optimized to reduce the installation cost of the thermal energy storage test facility.
Design considerations focus on the constructability of the design, ease of assembling the structure on site and selection of the most suitable construction
materials.
Operational strategies are developed to ensure that the outlet temperature, the temperature of the heat transfer fluid trough the fan and also the temperature
distribution through the rock pile do agree with the design specifications of the materials and the equipment used. Thermoclines defining the distribution of the temperature in the packed bed, round-the-clock cycle efficiency and characteristics of an idling storage system are investigated in this project.
Commissioning and experimental testing of various operational strategies are conducted in this project in order to find a suitable operational strategy that
can be used for this specific thermal energy storage that can make it feasible to use on a large scale.
The experimental results with the operation strategies implemented show that the thermal energy storage concept can be used for short term energy
storage with a usable energy recovery efficiency of 60%. The overall performance of the thermal energy storage system indicates that the concept under consideration in this project still needs to be improved to find an improved
solution for a low-cost thermal energy storage that is a viable option to utilize in industry. Current challenges to improve the volume efficiency of the packed bed of rocks and the energy recovery efficiency are identified in this project for future research.National Research Foundatio
An investigation into the potential cardioprotective effects of ghrelin in a rat model of chronic doxorubicin-induced cardiotoxicity
No full textNational Research Foundatio
Exploring South Africa’s southern frontier: A 20-year vision for polar research through the South African National Antarctic Programme
No full textAntarctica, the sub-Antarctic islands and surrounding Southern Ocean are regarded as one of the planet’s last remaining wildernesses, ‘insulated from threat by [their] remoteness and protection under the Antarctic Treaty System’. Antarctica encompasses some of the coldest, windiest and driest habitats on earth. Within the Southern Ocean, sub-Antarctic islands are found between the Sub-Antarctic Front to the north and the Polar Front to the south. Lying in a transition zone between warmer subtropical and cooler Antarctic waters, these islands are important sentinels from which to study climate change. A growing body of evidence now suggests that climatically driven changes in the latitudinal boundaries of these two fronts define the islands’ short- and long-term atmospheric and oceanic circulation patterns. Consequently, sub-Antarctic islands and their associated terrestrial and marine ecosystems offer ideal natural laboratories for studying ecosystem response to change. For example, a recent study indicates that the shift in the geographical position of the oceanic fronts has disrupted inshore marine ecosystems, with a possible impact on top predators. Importantly, biotic responses are variable as indicated by different population trends of these top predators. When studied collectively, these variations in species’ demographic patterns point to complex spatial and temporal changes within the broader sub-Antarctic ecosystem, and invite further examination of the interplay between extrinsic and intrinsic drivers
Managing conflict-generating invasive species in South Africa: Challenges and trade-offs
No full textBACKGROUND: This paper reviewed the benefits and negative impacts of alien species that are currently listed in the Alien and Invasive Species Regulations of the National Environmental Management: Biodiversity Act (Act no 10 of 2004) and certain alien species that are not yet listed in the regulations for which conflicts of interest complicate management.
OBJECTIVES: Specifically, it identified conflict-generating species, evaluated the causes and driving forces of these conflicts and assessed how the conflicts have affected management.
METHOD: A simple scoring system was used to classify the alien species according to their relative degree of benefits and negative impacts. Conflict-generating species were then identified and further evaluated using an integrated cognitive hierarchy theory and risk perception framework to identify the value systems (intrinsic and economic) and risk perceptions associated with each conflict.
RESULTS: A total of 552 alien species were assessed. Most of the species were classified as inconsequential (55%) or destructive (29%). Beneficial (10%) and conflict-generating (6%) species made a minor contribution. The majority (46%) of the conflict cases were associated with more than one value system or both values and risk perception. The other conflicts cases were based on intrinsic (40%) and utilitarian (14%) value systems.
CONCLUSIONS: Conflicts based on value and risk perceptions are inherently difficult to resolve because authorities need to balance the needs of different stakeholders while meeting the mandate of conserving the environment, ecosystem services and human well-being. This paper uses the identified conflict-generating species to highlight the challenges and trade-offs of managing invasive species in South Africa
Poverty reduction co-benefits through indigenous knowledge in climate change adaptation: a study within the eThekwini Municipality
No full textThe research utilizes mixed methods to discuss the incorporation of concepts of sustainable livelihoods for climate change adaptation in the eThekwini municipality, South Africa. The municipality identified and implemented climate change adaptation programs incorporating biodiversity, human elements of local economic development and poverty reduction. In poverty reduction co-benefits, the intervention incorporated communityfocused incentives, which mix local biodiversity awareness and efforts to compensate community members who are serving to protect their surrounding natural habitat. Although there is a noted shift in the inclusion of human development, little is reported around the utilization of indigenous knowledge in the project’s sustainability and future continuation within the community. The study recommended that climate change adaptation programs for environmental protection can be holistic if local communities’ cultural practices are incorporated for effective and sustainable interventionsNational Research Foundation (South Africa
A citizen science survey: perceptions and attitudes of urban residents towards vervet monkeys
No full textA diversity of indigenous and alien wildlife persists in suburbia, and provides residents with the opportunity to experience wildlife. Suburban gardens may serve as refugia and foraging grounds for many primate species allowing them to populate within a largely urbanized landscape. However, this has led to the increasing human interactions with them, resulting in conflict. Our study investigated the perceptions of suburban residents towards urban vervet monkeys Cercopithecus aethiops pygerythrus within the Msunduzi and Ethekwini municipalities, KwaZulu-Natal, South Africa. We assessed how these related to the monkeys’ presence, activities and interactions in residential gardens, and the value of wildlife to residents. Assessment was conducted through an online questionnaire survey. General attitudes of residents to vervet monkeys were canvassed by assessing the respondents’ level of active engagement in wildlife watching within their properties. We analyzed 603 surveys submitted online using logistic regression and ordinal regression models. We ascertained that vervet monkeys were disliked by 29% of residents due to their aggressiveness, destructive behaviour in gardens and households, and perceived threat to native wildlife. Frequency and duration of foraging vervet monkeys in residents’ gardens was influenced by the presence of pet dogs, fruiting trees, tall trees (>2 m), ratio of indigenous to alien vegetation of gardens, residency type, and active and passive food provisioning. Despite conflict, the majority of respondents appreciated urban wildlife (67%) and actively engaged in wildlife watching (88%), emphasizing the importance of incorporating human dimension values into the management of urban biodiversity. Our study highlights the value of citizen science in providing mechanisms for identifying priority management and conservation efforts at the highly complex human-wildlife interface in an urbanized landscape.National Research Foundation (South Africa
HOP expression is regulated by p53 and RAS and characteristic of a cancer gene signature
No full textThe Hsp70/Hsp90 organising protein (HOP) is a co-chaperone essential for client protein transfer from Hsp70 to Hsp90 within the Hsp90 chaperone machine. Although HOP is upregulated in various cancers, there is limited information from in vitro studies on how HOP expression is regulated in cancer. The main objective of this study was to identify the HOP promoter and investigate its activity in cancerous cells. Bioinformatic analysis of the −2500 to +16 bp region of the HOP gene identified a large CpG island and a range of putative cis-elements. Many of the cis-elements were potentially bound by transcription factors which are activated by oncogenic pathways. Luciferase reporter assays demonstrated that the upstream region of the HOP gene contains an active promoter in vitro. Truncation of this region suggested that the core HOP promoter region was −855 to +16 bp. HOP promoter activity was highest in Hs578T, HEK293T and SV40- transformed MEF1 cell lines which expressed mutant or inactive p53. In a mutant p53 background, expression of wild-type p53 led to a reduction in promoter activity, while inhibition of wild-type p53 in HeLa cells increased HOP promoter activity. Additionally, in Hs578T and HEK293T cell lines containing inactive p53, expression of HRAS increased HOP promoter activity. However, HRAS activation of the HOP promoter was inhibited by p53 overexpression. These findings suggest for the first time that HOP expression in cancer may be regulated by both RAS activation and p53 inhibition. Taken together, these data suggest that HOP may be part of the cancer gene signature induced by a combination of mutant p53 and mutated RAS that is associated with cellular transformation.National Research Foundation (South Africa
The two oceans project: Searching for novel carbohydrate sulfoconjugation enzymes
No full textMarine algae contain a wide range of carbohydrate-based bioactive compounds,
which promote extra-nutritional health benefits. In marine algae, the most sought
after bioactive compounds are sulfoconjugated polysaccharides (SPs) which have
the potential to be used as functional ingredients in the nutraceuticals industry. SPs
are of particular biological interest to human health and have been shown to exert
anti-inflammatory, anti-tumorigenic, immunostimulatory, and more recently anti-viral
activities. The specific biological properties of SPs are attributed to their monomer
composition, sulfate content, and sulfoconjugation pattern present on the sugar
backbone. The biochemical mechanisms through which these polysaccharides are
sulfoconjugated are well characterised in animals and are catalysed by a superfamily
of enzymes termed sulfotransferases (SULTs, EC 2.8.2). In vivo, SULTs are
responsible for the enzymatic process termed sulfoconjugation. This entails the
transfer of a sulfuryl group (SO3) from a donor molecule, classically 3’-
phosphoadenosine 5’-phosphosulfate (PAPS), to an acceptor molecule e.g. alcohol,
amine, sugar or phenolic compound.
The current state-of-the-art involves the isolation and purification of sulfoconjugated
compounds from marine organisms. These compounds are then tested for various
bioactivities (Hamed et al., 2015; Wijesekara et al., 2011). In contrast, here we used
a high-throughput RNA-seq approach to identify 18 putative SULT transcripts and
subsequently isolated one carbohydrate SULT. Eight of the SULTs identified from
the P. corallorhiza transcriptome had a Sulfotransfer_1 domain. However, four of the
eight Sulfotransfer_1 SULTs also had a Sulfotransfer_3 domain. Additionally, seven
SULTs had a Sulfotransfer_2 domain, with one also possessing a Gal-3-O_sulfotr
domain. The SULTs identified with overlapping domains were not exclusively
assigned to any one SULT family, as they had statistically significant homology
(<0.05) to either the Sulfotransfer_1 and Sulfotransfer_3 or the Sulfotransfer_2 and
the Gal-3-O_sulfotr domain containing SULT entries, respectively. Additionally, this
approach included the diurnal sampling of a ubiquitously distributed red algal species, Plocamium corallorhiza, as a generic representative of the Rhodophyta
phylum. A diurnal differential gene expression analysis was used to assess potential
differences in gene expression, specifically with regard to galactan biosynthesis.
Ultimately, 639 nocturnally differentially expressed genes (DEGs) were identified.
However, no DEGs relating to galactan biosynthesis as it relates to starch and
sucrose, galactose or sulfur metabolism pathways, were present within the 639
DEGs.National Research Foundatio
Jamaica / South Africa joint science and technology cooperation call for joint research proposals for 2018-2020 projects
No full textIn 2016, South Africa (through the Department of Science and Technology) and Jamaica (through the Ministry of Science, Energy and Technology) signed an Agreement on Science and Technology cooperation which led to the adoption of a Programme of Activity (PoA) on 17 November 2016. The PoA identifies the NRF and the National Commission on Science and Technology (NCST) as the implementing agencies for this Agreement. Both the NRF and the NCST are hereby pleased to announce this first call for 3-year joint research projects (starting from January 2018 and ending December 2020) in Indigenous Knowledge Systems and Water Research between South African and Jamaican researchers