Deep impact: the role of architecture as narrative medium

The following document deals with the issue of the Narrative Role of Architecture in the representation of knowledge in Museum Architecture and landscape interpretation. The aim of the research is to extract a set of principles that can be used in the design of a visitors’ centre to a meteor crater impact site at the Vredefort Dome Conservancy World Heritage site, north-west of the town of Parys. The research is aimed at investigating changes in the representation of knowledge in museum architecture by looking at Psarra 2009’s comparisons of museum design, from early 19th century museum representations of Victorian knowledge and the development of Natural History museums to current issues facing the design of Natural Science exhibitions. It Includes the museum as a form of entertainment and spectacle, content as a whole and the inter-relationships between objects on display and the architecture that houses it. The significance of the research is to establish current thought on the question of the Museum in terms of the representation of knowledge as a means of educating the public and promoting a sense of respect for heritage and a positive attitude towards conservation. Museums have often made use of narrative architecture to help convey information to the public. These principles are summarised and applied to the design of a visitors’ centre for a meteor impact site. The final design explores geological concepts in order to tell the story of the Vredefort Meteor impact sit

Technical note The formulation of synthetic domestic wastewater sludge medium to study anaerobic biological treatment of acid mine drainage in the laboratory

Requirements for successful biological treatment of acid mine drainage (AMD) rely on the reduction of sulphates by microorganisms using a suitable organic carbon source. Various carbon sources, such as domestic wastewater sludge, have previously been used in the semi-passive biological treatment of  AMD. Domestic wastewater sludge is however highly variable in its composition, making laboratory  experimentation difficult. Synthetic medium was therefore formulated based on the chemical oxygen demand (COD) and the biological degradable organic matter (BOD) of domestic wastewater sludge. Four synthetic media compositions were formulated consisting of different ratios of meat extract,  vegetable extract, sodium chloride, potassium phosphate, urea, ammonium chloride, iron sulphate, magnesium sulphate and glucose. The media composition with BOD and COD measurements closest to that of anaerobic domestic wastewater sludge was selected for further studies. The combination of AMD to synthetic wastewater sludge in 3 ratios was determined for COD and sulphate reduction in bioreactors over a period of 90 d. The highest reduction of 86.76% in COD and 99.22% in sulphate content were obtained in a 1:1 AMD: synthetic domestic wastewater sludge (SDWWS) ratio that calculated to a COD/sulphate ratio of 3.Keywords: acid mine drainage, synthetic domestic wastewater sludge, sulphates, CO

The state of green technologies in South Africa

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Polyphasic taxonomic characterization of lactic acid bacteria isolated from spontaneous sorghum fermentations used to produce ting, a traditional South African food

Ting, an indigenous cooked fermented food made from sorghum flour, is consumed extensively in South Africa. Due to the spontaneous nature of the sorghum fermentation considerable variations in the sensory and microbial quality of the end-product may occur, thus hampering large-scale production of this food. The use of starter cultures purified from the fermented sorghum may be an alternative approach to obtain ting of consistent quality. The aim of this study was therefore to identify the lactic acid bacteria (LAB) associated with ting fermentation using a polyphasic approach. Phenotypic characterization and sequence analysis of the genes encoding the 16S subunit of the ribosomal RNA (rrs) and phenylalanyl tRNA synthase (pheS) were used. The results of these analyses showed that ting fermentation involved at least three different species of LAB, i.e. Lactobacillus fermentum, L. plantarum and L. rhamnosus. To our knowledge, this is the first report of polyphasic taxonomic characterization of LAB from this food. This research forms an essential first step towards the development of relevant starter cultures to produce ting of consistent quality

Mechanism of Microcystis aeruginosa death upon exposure to Bacillus mycoides

Electron microscopy observations revealed at least two mechanisms of Microcystis aeruginosa cell death upon exposure to Bacillus mycoides, i.e. cell membrane lysis and shadowing of algal cells leading to photoinhibition. There were ultra-structural changes that occurred in bacteria treated M. aeruginosa cells. SEM images showed swollen M. aeruginosa cells due to cell membrane damage and increased osmotic pressure. The production of intracellular stress related structures by M. aeruginosa indicated cell stress as a result of bacteria causing shadowing and photo-inhibition affecting the photosynthetic system. There is evidence, which showed that B. mycoides B16 might be an ectoparasite during the lysis of Microcystis cells and exhibit multicellular forms that are Bdellovibrio-like bacteria during the last stages lysis of Microcystis cells in order to survive an adverse external environment that was nutrient limited. The mechanism of cyanobacterial lysis may involve changes in ultrastructure of M. aeruginosa, possibly affecting energy sources and the photosynthetic system after exposure to bacteria. This may lead to the death of the cyanobacteria after exhaustion of energy sources and loss of nutrients to the predator bacteria, B. mycoides B16. A better understanding of the interactions between B. mycoides 16 and M. aeruginosa is important for the development of a biological control agent and ultimately the management of harmful algal blooms dominated by M. aeruginosa.NRF and University of Pretoria (UP)http://www.elsevier.com/locate/pcenf201

Light and electron microscope assessment of the lytic activity of Bacillus on Microcystis aeruginosa

During the screening of lytic bacteria, plaques were obtained on Microcystis lawns. In the plaques, at least five distinct morphotypes of bacteria were found. The plumb rod-shaped bacilli were the most abundant and were found aggregated around unhealthy Microcystis cells and were the probable cause of deflation and lysis. These bacteria may have utilized the cyanobacteria cell contents as their nutrient source. In contrast to the control areas, the cyanobacteria cells were healthy and did not show any visible distortion of cell structure. The presence and possible role of the free-bacteria, that is, bacteria that were not attached or associated with the cyanobacteria in the plaque is not clear. Maybe their function is to scavenge the skeletal remains of Microcystis cells. Bacillus mycoides B16 were found to have a lytic effect on Microcystis cells. Scanning electron micrographs (SEM) images of B. mycoides B16 did not reveal any unique attachments that may have allowed them to adhere to Microcystis cells. The Microcystis cells were exposed to copper, B. mycoides B16 and Triton X-100, in order to ascertain the level of cell membrane damage. The membrane cell damage was most severe with copper stripping the entire Microcystis cell membrane leaving a honeycomb skeletal structure and B. mycoides B16, leaving perforations on the cell membrane. The electron microscopy observations appeared to reveal at least two mechanisms of Microcystis lysis (contact and parasitism). The light and electron microscope (LEM) observations did not reveal any endoparasitism of B. mycoides B16 or Bdellovibrio-like behaviour.The authors wish to acknowledge the NRF and University of Pretoria (UP) for the financial support for the study.http://www.academicjournals.org/AJ

The effect of ultrasound at 256 KHz on Microcystis aeruginosa, with and without gas vacuoles

The effect of ultrasound on the growth of M. aeruginosa confirmed to contain gas vacuoles and on a laboratory culture with no gas vacuoles was investigated. Both cultures were treated continuously for 9 d with an ultrasonic flow device. To evaluate the influence of ultrasound during the treatment, the chlorophyll-a concentration was measured daily. Furthermore, changes in culture characteristics, e.g., flotation and gas vesicle formation, were determined. The results showed that, in contrast to the control, both ultrasonic-treated cultures had a lower chlorophyll-a concentration and cell aggregates were disrupted. Transmission electron microscopy confirmed a collapse of gas vacuoles in the environmental culture, while the laboratory culture, which did not contain gas vacuoles, showed many membrane-damaged cells. It was concluded that ultrasonic treatment of M. aeruginosa caused the disruption of gas vacuoles and destruction of cell membranes.http://www.wrc.org.zaam201

NEPAD Southern African Water Centres of Excellence - Report on task JLP1.1 and JLP1.2

The NEPAD SANWATCE network investigation in collaboration with the European Commission Joint Research Centre looks into the skills shortages that exist in the SADC region in water resources management, and further discusses how the Water Centres of Excellence could better address sector expertise and advocacy for sector development in the region.JRC.H.1-Water Resource

The formulation of synthetic domestic wastewater sludge medium to study anaerobic biological treatment of acid mine drainage in the laboratory

CITATION: Van den Berg, M. F., Botes, M. & Cloete, T. E. 2016. The formulation of synthetic domestic wastewater sludge medium to study anaerobic biological treatment of acid mine drainage in the laboratory. Water SA, 42(2):350-354, doi:10.4314/wsa.v42i2.18.The original publication is available at http://www.wrc.org.zaRequirements for successful biological treatment of acid mine drainage (AMD) rely on the reduction of sulphates by microorganisms using a suitable organic carbon source. Various carbon sources, such as domestic wastewater sludge, have previously been used in the semi-passive biological treatment of AMD. Domestic wastewater sludge is however highly variable in its composition, making laboratory experimentation difficult. Synthetic medium was therefore formulated based on the chemical oxygen demand (COD) and the biological degradable organic matter (BOD) of domestic wastewater sludge. Four synthetic media compositions were formulated consisting of different ratios of meat extract, vegetable extract, sodium chloride, potassium phosphate, urea, ammonium chloride, iron sulphate, magnesium sulphate and glucose. The media composition with BOD and COD measurements closest to that of anaerobic domestic wastewater sludge was selected for further studies. The combination of AMD to synthetic wastewater sludge in 3 ratios was determined for COD and sulphate reduction in bioreactors over a period of 90 d. The highest reduction of 86.76% in COD and 99.22% in sulphate content were obtained in a 1:1 AMD: synthetic domestic wastewater sludge (SDWWS) ratio that calculated to a COD/sulphate ratio of 3.Publisher's versio

Relationship between plant growth and organic acid exudates from ectomycorrhizal and non-ectomycorrhizal Pinus patula

Plant–mycorrhizal interaction is an important association in the ecosystem with significant impacts on the physical, biological and chemical properties of the soil. In the present study, potential relationships that exist between organic acid production by ectomycorrhizal pine seedlings and plant parameters in the absence of any significant environmental stress were investigated. The aim of the study was to investigate the contribution of organic acid production to plant growth. Four different ectomycorrhizal fungi were used in a mycorrhizal synthesis experiment to colonise roots of Pinus patula. Ectomycorrhizal and nonectomycorrhizal plants were used in a pot trial experiment that lasted for 24 weeks. After harvesting, plant materials as well as soil samples underwent different analyses, which included the determination of pH, organic acids, plant biomass, and foliar and root phosphorus and potassium. The results indicated a significant interaction (P < 0.0001) between fungal type and organic acid production. This reflects the influence of fungal type on organic acid production. However, it was observed that organic acids secreted into the soil do not have a direct link to the quantity of nutrients detected in either the root or shoot, but seemed to positively influence plant growth as reflected in the result from root and shoot biomass.http://www.tandfonline.com/loi/tjps202016-06-04hb201