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The Stephani universe is an inhomogeneous alternative to ΛCDM. We show that the exotic fluid driving the Stephani exact solution of Einstein’s equations is an unusual form of k-essence that is linear in “velocity”. Much as the Stephani universe can be embedded into (a section of) flat 5-d Minkowski space-time, we show that the k-essence obtains through dimensional reduction of a 5-d strongly coupled non-linear “electrodynamics” that, in the empty Stephani universe, corresponds to space filling magnetic branes in string/M-theory.

(2020). The house of Tshatshu: power, politics and chiefs north-west of the Great Kei River c1818–2018. Anthropology Southern Africa: Vol. 43, No. 4, pp. 268-270.

The recently completed report on “The removal of urban litter from stormwater conduits and streams” (by Armitage et al.) notes that little data is available on the nature and quantity of litter that finds its way into the stormwater drainage systems. The Council for Scientific and Industrial Research (CSIR) estimated in 1991 that 780 000 tonnes of waste a year was entering the drainage systems of South Africa, representing a potential removal cost in excess of two billion rand. There is thus a considerable need for finding ways to reduce litter loadings through better catchment management. Although suggestions have been made as to how this might be achieved, there is very little scientifically verified data from anywhere in the world to show that any of these proposed methods would be effective in South Africa. Only through an improved knowledge of the litter loadings in South African urban drainage systems can appropriate strategies to reduce litter loadings be arrived at. This improved knowledge is one of the twin objectives of the Water Research Commission Project No. K5/1051 entitled “The reduction of urban litter in drainage systems through integrated catchment management.” Under this project a three-year monitoring programme has been instituted in nine catchments covering a range of different land uses, socio-economic levels and densities in the Cape Metropolitan Area. This paper focuses on the methodology behind the monitoring programme and the objectives it is hoped to achieve.

A previous South African study looked at the removal of litter from the drainage systems once it was already there. Yet the litter problem cannot be addressed in an effective and sustainable manner without an effective integrated catchmentwide litter management strategy. This strategy should include planning controls, source controls, and structural controls. The main focus of this paper is the source control of urban litter. It reviews international and local practice, and reports on the results of a two-year monitoring programme conducted in nine pilot catchments covering a range of different land uses, socio-economic levels and population densities in the City of Cape Town. It proposes preliminary guidelines for the reduction of urban litter loads entering the drainage system by dealing with litter pollution at its source. Keywords: Litter management, Stormwater drainage systems, Water quality management, Source controls, Reduction of urban litter, Solid waste pollution control WaterSA Vol.30(4) 2004: 483-492

The wash-off of solid waste into the drainage systems of urban areas is not only unsightly; it seriously interferes with aquatic life in the receiving streams, rivers, lakes and oceans. Litter management in South Africa is currently, however, severely hindered by the lack of good quality data on the quantities and types of urban litter emanating from different types of landuse. This paper describes a monitoring programme that was implemented between 2000 and 2002 in nine subcatchments representing various land uses and demographic profiles located within the boundaries of the City of Cape Town. Measured quantities of urban litter, vegetation, and building debris are given for each of the nine subcatchments. These data are then used as input to a GIS-based model of the City of Cape Town in order to estimate the quantity of urban litter that is currently entering the drainage systems of that city. Key Words: Litter management, Stormwater drainage systems, Water quality management, Quantity of litter WaterSA Vol.30(4) 2004: 469-482

There is a paucity of data on the nature and quantity of urban litter (alternatively called trash or rubbish) that finds its way into the stormwater drainage s…

South Africa generates in excess of 40 million tonnes of solid waste every year - mostly of domestic origin. More than 780000 tonnes of this is washed into the…