60 research outputs found
The role of the private sector in providing gap housing in Johannesburg
A research report submitted to the faculty of Engineering and the Built Environment, University of the Witwatersrand, Johannesburg, in partial fulfillment of the requirements of the degree of Masters of the Built Environment in Housing.
Johannesburg, 2018South Africa has a significant housing shortage and even though the government has provided in excess of three million subsidised houses to beneficiaries since 1994, a shortage of 2.1 million units still exists. While households earning less than R3 500 qualify for a fully subsidised house, the most affordable newly built house on the market in Johannesburg is only affordable to households earning about R14 300. Therefore, a gap in the housing market exists between those too rich to qualify for a full housing subsidy and those too poor to access formal bonded housing.
A partial subsidy, called the Finance-Linked Individual Subsidy Programme (FLISP), is available to households earning less than R15 000 to help them access housing in the formal market. Although private developers are developing houses affordable to households earning less than R15 000, uptake of the subsidy has been limited. Johannesburg has roughly 385 000 households in the gap market.
This study seeks to establish what role the private sector currently plays in providing gap housing in Johannesburg. A qualitative study was done by interviewing various developers who are involved with gap housing developments, using semi-structured interviews and email correspondence. Furthermore, this study aims to establish what perceptions developers have of the market, what difficulties they face, what barriers exist to entering the market and how private companies help their employees in accessing gap housing.
It was found that developers have a positive view of the market. Many echoed the view that the market in Johannesburg is vast, growing and that there are plentiful opportunities. There are, however, factors that make delivering less expensive houses more difficult. Bulk service contributions, especially, are becoming excessive, while the time taken to approve new townships can lead to unnecessary holding costs. Poor access to development finance is seen as prohibiting new developers from entering the market. Developers are aware of only a handful of private companies involved with assisting their employees to access gap housing.
Although there are numerous gap housing developments in Johannesburg and many more planned, relatively few FLISP subsidies have been granted. These subsidies are tied to access to traditional mortgage finance. Fewer and fewer mortgages in the gap housing range have been given in recent years and if more houses are to be delivered, housing finance should be made more accessible to lower income earners.MT 201
Creative synergy : using community theatre and appreciative inquiry for young people's critical participation in HIV prevention and education
This paper positions Community Theatre as an agency for development and education based on the educational
principles of Freire and Boal’s Theatre for Development. The paper argues that Appreciative Inquiry can enrich the
practice of Community Theatre by approaching HIV and AIDS education as an asset-based, participatory, inclusive,
learner-centred approach. The paper hypothesises that the infusion of the 4-D process of Appreciative Inquiry into
Community Theatre processes aimed at HIV and AIDS education will enhance young people’s agency as active
participants and agents of change in their communities beyond the didactic notions inherent in ABC education
approaches to HIV prevention. The paper argues that this approach can encourage meaningful participation and
critical consciousness amongst young people in the HIV prevention response.http://www.tandfonline.com/loi/uytj20hb2016Dram
Epidemic Levels of Drug Resistant Tuberculosis (MDR and XDR-TB) in a High HIV Prevalence Setting in Khayelitsha, South Africa
BACKGROUND: Although multidrug-resistant tuberculosis (MDR-TB) is emerging as a significant threat to tuberculosis control in high HIV prevalence countries such as South Africa, limited data is available on the burden of drug resistant tuberculosis and any association with HIV in such settings. We conducted a community-based representative survey to assess the MDR-TB burden in Khayelitsha, an urban township in South Africa with high HIV and TB prevalence. METHODOLOGY/PRINCIPAL FINDINGS: A cross-sectional survey was conducted among adult clinic attendees suspected for pulmonary tuberculosis in two large primary care clinics, together constituting 50% of the tuberculosis burden in Khayelitsha. Drug susceptibility testing (DST) for isoniazid and rifampicin was conducted using a line probe assay on positive sputum cultures, and with culture-based DST for first and second-line drugs. Between May and November 2008, culture positive pulmonary tuberculosis was diagnosed in 271 new and 264 previously treated tuberculosis suspects (sample enriched with previously treated cases). Among those with known HIV status, 55% and 71% were HIV infected respectively. MDR-TB was diagnosed in 3.3% and 7.7% of new and previously treated cases. These figures equate to an estimated case notification rate for MDR-TB of 51/100,000/year, with new cases constituting 55% of the estimated MDR-TB burden. HIV infection was not significantly associated with rifampicin resistance in multivariate analyses. CONCLUSIONS/SIGNIFICANCE: There is an extremely high burden of MDR-TB in this setting, most likely representing ongoing transmission. These data highlight the need to diagnose drug resistance among all TB cases, and for innovative models of case detection and treatment for MDR-TB, in order to interrupt transmission and control this emerging epidemic
Comparison of laboratory costs of rapid molecular tests and conventional diagnostics for detection of tuberculosis and drug-resistant tuberculosis in South Africa.
BACKGROUND: The World Health Organization has endorsed the use of molecular methods for the detection of TB and drug-resistant TB as a rapid alternative to culture-based systems. In South Africa, the Xpert MTB/Rif assay and the GenoType MTBDRplus have been implemented into reference laboratories for diagnosis of TB and drug-resistance, but their costs have not been fully elucidated. METHODS: We conducted a detailed reference laboratory cost analysis of new rapid molecular assays (Xpert and MTBDRplus) for tuberculosis testing and drug-resistance testing in South Africa, and compared with the costs of conventional approaches involving sputum microscopy, liquid mycobacterial culture, and phenotypic drug sensitivity testing. RESULTS: From a laboratory perspective, Xpert MTB/RIF cost 23.46/sample, compared to $16.88/sample using conventional automated liquid culture-based methods. Laboratory costs of Xpert and MTBDRplus were most influenced by cost of consumables (60-80%). CONCLUSIONS: At current public sector pricing, Xpert MTB/RIF and MTBDRplus are comparable in cost to mycobacterial culture and conventional drug sensitivity testing. Overall, reference laboratories must balance costs with performance characteristics and the need for rapid results
The Impact of Expanded Testing for Multidrug Resistant Tuberculosis Using Geontype MTBDRplus in South Africa: An Observational Cohort Study
Globally, multidrug resistant tuberculosis (MDR-TB) remains underdiagnosed. The Genotype MTBDRplus®, a rapid drug susceptibility testing (DST) assay used to detect resistance to isoniazid and rifampicin in the diagnosis of MDR-TB, has good diagnostic accuracy, but its impact on patient outcomes in routine practice is unproven. We assessed the clinical impact of routine DST using MTBDRplus in a single health district in South Africa
Fungal diversity associated with the mycorrhizosphere soil of Brachycorythis conica subsp. transvaalensis, a critically endangered and endemic terrestrial orchid from South Africa
DATA ACCESSIBILITY : The high-throughput sequencing data generated in this study is available at the NCBI Sequence Read Archive (https://submit.ncbi.nlm.nih.gov/ subs/sra/) under the accession number PRJNA693177.The Albertina Sisulu orchid, Brachycorythis conica subsp. transvaalensis is a critically endangered terrestrial orchid with a single population remaining in the Gauteng Province of South Africa. For the conservation of this endemic orchid, several strategies are being implemented such as protection of habitat, identifying pollinators and in vitro propagation. For symbiotic germination, it is essential to identify the mycorrhizal associates of this orchid using non-destructive sampling. In this study, high-throughput sequencing was used to catalogue and compare the diversity of fungi associated with the mycorrhizosphere of this orchid and non-mycorrhizosphere soils collected from the same coordinates. Bioinformatics and statistical analyses of the data showed that, despite the substantial overlap in the community composition of fungi associated with these two soil types, several exclusive fungal species were identified from the mycorrhizosphere of the orchid. These included an assortment of potential orchid mycorrhizal species from the orders Agaricales, Cantharellales and Sebacinales. This study provides the first insight into the soil fungal diversity associated with the mycorrhizosphere of this critically endangered orchid. In the future, data from this study can be used for optimising conservation measures and isolation of suitable mycorrhizal species required for in vitro symbiotic germination of this orchid.The NRF Foundational Biodiversity Information Programme, the International Partnergroup Program of the Max Planck Society and the NRF SARChI Chair in Fungal Genomics.http://www.elsevier.com/locate/sajbhj2023BiochemistryForestry and Agricultural Biotechnology Institute (FABI)GeneticsMicrobiology and Plant PathologyZoology and Entomolog
Uncovering the mycorrhizal community of two Habenaria orchids in South Africa
Southern Africa is a biodiversity hotspot for a variety of orchids, including Habenaria. However, we know very little about the orchid mycorrhizae that are associated with these orchids. To bridge this gap, we compared the community of orchid mycorrhizae that are associated with two indigenous Habenaria species, H. barbertoni and H. epipactidea, using a high-throughput sequencing platform. We selected these two orchids because their distribution zones overlap in South Africa. Furthermore, H. barbertoni is endangered, whereas H. epipactidea is not. We hypothesised that the mycorrhizal diversity and composition linked with the roots of these two orchids would overlap, but that some distinct fungal taxa would exist, and these distinct fungi would include unusual taxa. Analyses of the DNA sequence data revealed that the two orchids shared 35 fungal OTUs. Twenty-four and seventeen OTUs were exclusively detected in the roots of H. barbertoni and H. epipactidea, respectively. Mycorrhizal fungi from the rust lineage Atractiellales (Atractiellomycetes, Pucciniomycotina) were only detected in the roots of the endangered H. barbertoni, which represents the first report of these fungi associated with orchids outside of the Andean rainforest. Our findings increase knowledge of the diversity of mycorrhizae associated with indigenous orchids on the African continent.The South African National Research Foundation, the Max Planck Society's International Partnergroup Program and National Research Foundation SARChI Chair in Fungal Genomics.http://www.elsevier.com/locate/sajbhj2023BiochemistryForestry and Agricultural Biotechnology Institute (FABI)GeneticsMicrobiology and Plant PathologyZoology and Entomolog
A subset of circulating blood mycobacteria-specific CD4 T cells can predict the time to Mycobacterium tuberculosis sputum culture conversion
We investigated 18 HIV-negative patients with MDR-TB for M. tuberculosis (Mtb)- and PPD-specific CD4 T cell responses and followed them over 6 months of drug therapy. Twelve of these patients were sputum culture (SC) positive and six patients were SC negative upon enrollment. Our aim was to identify a subset of mycobacteria-specific CD4 T cells that would predict time to culture conversion. The total frequency of mycobacteria-specific CD4 T cells at baseline could not distinguish patients showing positive or negative SC. However, a greater proportion of late-differentiated (LD) Mtb- and PPD-specific memory CD4 T cells was found in SC positive patients than in those who were SC negative (p = 0.004 and p = 0.0012, respectively). Similarly, a higher co-expression of HLA-DR + Ki67 + on Mtb- and PPD-specific CD4 T cells could also discriminate between sputum SC positive versus SC negative (p = 0.004 and p = 0.001, respectively). Receiver operating characteristic (ROC) analysis revealed that baseline levels of Ki67 + HLA-DR + Mtb- and PPD-specific CD4 T cells were predictive of the time to sputum culture conversion, with area-under-the-curve of 0.8 (p = 0.027). Upon treatment, there was a significant decline of these Ki67 + HLA-DR + T cell populations in the first 2 months, with a progressive increase in mycobacteria-specific polyfunctional IFNγ + IL2 + TNFα + CD4 T cells over 6 months. Thus, a subset of activated and proliferating mycobacterial-specific CD4 T cells (Ki67 + HLA-DR + ) may provide a valuable marker in peripheral blood that predicts time to sputum culture conversion in TB patients at the start of treatment
The mechanical and volumetric behaviour of sisal fibre reinforced concrete blocks
Thesis (MScEng)--Stellenbosch University, 2013.ENGLISH ABSTRACT: Natural fibre reinforced concrete (NFRC) is a type of concrete that has become of particular interest
in recent years, due to its potential for being used as a sustainable and economically viable building
material. Natural fibres are often cheap and widely available in developing nations. Sisal is one such
fibre predominantly grown in Brazil and has been identified as having the potential to be
commercially cultivated in Southern Africa.
The durability of sisal fibres in a cementitious environment tends to be adversely affected due to the
high alkalinity of pore water and the presence of calcium hydroxide.
This research dealt with the use of sisal fibre reinforced concrete (SFRC) blocks. It focused on the
mechanical and volumetric properties of blocks with varying fibre and condensed silica fume content
(CSF).
Two different SFRC blocks were produced (solid and hollow) using an average fibre length of 10 mm.
Two matrix types were used: one using a 70:30 cement:fly-ash ratio and another using a 60:30:10
cement:fly-ash:CSF ratio by weight. Samples of each matrix type were prepared with 0, 0.5 and 1%
fibre content by volume.
Hollow blocks were tested for compressive strength and capillary water absorption, while solid
blocks were tested for compressive strength, flexural strength, capillary water absorption,
dimensional stability, drying shrinkage, density, total water absorption and void content. All tests
were performed on samples with an age of 28 days. Solid block compressive tests were also
performed on samples with an age of 7 days.
The hollow blocks had significantly lower average compression strength than the solids, but an
increase in fibre content caused a slight increase in strength.
For solid blocks, it was found that the addition of natural fibres decreases the strength, although a
partial substitution of cement with CSF, in conjunction with fibres, did increase the strength relative
to blocks without CSF. The flexure strength was also lowered somewhat by the addition of fibres, but
an increase in ductility was noted, although not quantified. The addition of CSF to fibre-containing blocks led to an increase in capillary water absorption, but a
decrease in absorption through immersion. This shows that the addition of CSF does significantly
alter the pore system of a cementitious matrix reinforced with natural fibres. Also, the dimensional stability increased with the addition of CSF and fibres. The same can be said for
drying shrinkage. Even though an increase in fibre and CSF caused samples to shrink more under
drying, they were more stable under cycles of wetting and drying.
It was concluded that the addition of fibres to a matrix had a detrimental effect on strength,
although ductility did increase. The volumetric properties of concrete were also adversely affected by
the addition of fibres, although dimensional stability was improved. The partial substitution of
cement with CSF did improve many of the mechanical and volumetric properties of samples
containing sisal fibre.AFRIKAANSE OPSOMMING: Natuurlike vesel bewapende beton (NVBB) is ’n tipe beton wat onlangs heelwat belangstelling ontlok
het weens die potensiaal om gebruik te word as ‘n volhoubare en ekonomiese haalbare boumateriaal.
Natuurlike vesels is dikwels baie goedkoop en wyd beskikbaar in ontwikkelende lande. Sisal is een so
‘n vesel wat verkry word vanaf die blare van ’n garingboom. Die plant word hoofsaaklik in Brasilië
verbou en is al uitgewys weens sy potensiaal om op kommersiële skaal in Suidelike Afrika verbou te
word.
Die duursaamheid van sisal vesels is geneig om nadelig geaffekteer te word in die teenwoordigheid
van kalsium hidroksied en ’n hoë-alkali omgewing, soos gevind in die porie-water van beton.
Hierdie navorsing handel oor die gebruik van sisal vesel bewapende beton (SVBB) boublokke. Dit
fokus op die meganiese- en duursaamheids eienskappe van blokke met verkillende inhoude van vesel
en gekondenseerde silika dampe (GSD).
Twee verskillende SVBB blokke is geproduseer (solied en hol) deur gebruik te maak van 10 mm vesels.
Twee matriks tipes is gebruik: een met ’n 70:30 sement:vliegas verhouding en een met ’n 60:30:10
sement:vliegas:GSD verhouding, volgens gewig. Blokke van elke matriks tipe is geproduseer met 0,
0.5 en 1% vesel inhoud, volgens volume.
Hol blokke is getoets vir druksterkte en kapillêre water absorpsie, terwyl soliede blokke getoets is vir
druksterkte, buigsterkte, kapillêre water absorpsie, dimensionele stabiliteit, krimp onder uitdroging,
digtheid, totale water absorpsie en luginhoud. Alle toetse is gedoen op blokke met ’n ouderdom van
28 dae. Druktoetse is ook gedoen op soliede blokke met ’n ouderdom van 7 dae.
Die hol blokke het ’n aansienlike laer gemiddelde druksterkte as die soliede blokke gehad, maar ’n
toename in veselinhoud het gelei tot ’n effense verhoging in druksterkte.
’n Toename in veselinhoud van soliede blokke het gelei tot ’n afname in druksterkte, alhoewel ’n
gedeeltelike vervanging van sement met GSD gelei het tot ’n hoër druksterkte vir blokke met vesels.
Die buigsterkte van soliede blokke het ook afgeneem met ’n verhoging in veselinhoud. ’n Verhoging
in duktiliteit is waargeneem met ’n toename in veselinhoud, alhoewel dit nie gekwantifiseer is nie. Die toevoeging van GSD tot blokke bevattende vesels het gelei tot ’n verhoging in kapillêre water
absorpsie, maar ’n verlaging in totale water absorpsie. Dit kan daarop wys dat die toevoeging van
GSD die poriestelsel van NVBB noemenswaardig verander. Beide die dimensionele stabiliteit en krimp onder uitdroging het toegeneem met die toevoeging van
GSD en vesels tot die blokke. Dus, die toevoeging het gelei tot ’n hoër krimpvervorming tydens
uitdroging en ’n hoër stabiliteit tydens nat/droog siklusse.
Daar is tot die gevolgtrekking gekom dat die toevoeging van sisal vesels tot ’n beton blok oor die
algemeen ’n negatiewe effek het op sterkte, alhoewel duktiliteit toeneem. Die volumetriese
eienskappe van beton word ook negatief geaffekteer met die toevoeging van sisal vesels, alhoewel
dimensionele stabiliteit verbeter. Die gedeeltelike vervanging van sement met GSD lei tot die
verbetering van beide meganiese en volumetriese eienskappe van beton blokke wat sisal vesels
bevat
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