Replacing the Nation: South Africa's passive revolution? [Audio]
Speaker(s): Professor Gillian Hart | In the light of the conflicting forces that have unfolded in South Africa over the last decade, Gillian Hart takes a fresh look at the nation’s transition from apartheid. Based on Professor Hart’s forthcoming book, this lecture will explore the simultaneous processes of South African de-nationalization, re-nationalization and ‘elite pacting’, before examining how this fits within contemporary debates over passive revolution. Gillian Hart is Professor
Music Visualization using Independent Component Analysis
Rene Castro
Elec 301 Project on Music Visualization Using Independent Component Analysis
Some Rights Reserved
SMU Lyle Students: "I ROBOT"
First year engineering students in SMU's Lyle School worked in multi-disiplinary teams during their fall 2012 design class to build robots capable of duplicating the water testing and remediation work Lyle faculty and students are doing in United Nations refugee camps. "When it actually works, it's amazing!" said Lyle student Jordan Kayse. This video captures all the energy of "demo day" in SMU Lyle's Innovation Gym.
Hearing Yourself Hear
Listen in as Artist Jacob Kirkegaard tells of his journey to hear himself hear. With the aid of researchers in Copenhagen, Kirkegaard generates an artificial tone in his own ear by playing two tones at a precise ratio. He has developed this phenomenon into an interactive sound piece he calls Labyrinthitis. (07:13)
4.4 Reducing nutrient availability Once nutrients are in an ecosystem, it is usually much harder and more expensive to remove them than tackle the eutrophication at source. The main methods available are: precipitation (e.g. treatment with a solution of aluminium or ferrous salt to precipitate phosphates); removal of nutrient-enriched sediments, for example by mud pumping; and removal of biomass (e.g. harvesting of common reed) and using it for thatchi
4.4.2 Phosphate stripping It has been estimated that up to 45% of total phosphorus loadings to freshwater in the UK comes from sewage treatment works. This input can be reduced significantly (by 90% or more) by carrying out phosphate stripping. The effluent is run into a tank and dosed with a product known as a precipitant, which combines with phosphate in solution to create a solid, which then settles out and can be removed. It is possible to use aluminium salts as a precipitant, but the resulting sludge contains tox
4.3 Reducing the nutrient source Europe is the continent that has suffered most from eutrophication, and increasing efforts are being made to restore European water bodies damaged by nutrient enrichment. If the ultimate goal is to restore sites where nature conservation interest has been damaged by eutrophication, techniques are required for reducing external loadings of nutrients into ecosystems. Although algal production requires both nitrogen and phosphorus supplies, it is usually sufficient to reduce only one major
3.2.2 Domestic detergents Domestic detergents are a major source of phosphorus in sewage effluents. Phosphates are used as a ‘builder’ in washing powders to enhance the efficiency of surfactants by removing calcium and magnesium to make the water ‘softer’. In 1992, the UK used 845 600 tonnes of detergent of various types, all of which have different effects on the environment. Estimates of the relative contribution of domestic detergents to phosphorus build-up in Britain's watercourses vary from 20–60%. The
3.1.1 Phosphorus Phosphorus has a number of indispensable biochemical roles and is an essential element for growth in all organisms, being a component of nucleic acids such as DNA, which hold the code for life. However, phosphorus is a scarce element in the Earth's crust and natural mobilization of phosphorus from rocks is slow. Its compounds are relatively insoluble, there is no reservoir of gaseous phosphorus compounds available in the atmosphere (as there is for carbon and nitrogen), and phosphorus is also
2.4.2 Saltmarshes Marsh plant primary production is generally nitrogen limited, so saltmarsh vegetation responds readily to the artificial eutrophication that is now so common in nearshore waters. Eutrophication causes marked changes in plant communities in saltmarshes, just as it does in freshwater aquatic and terrestrial systems. Biomass production increases markedly as levels of eutrophication increase. Increases in the nitrogen content of plants cause dramatic changes in populations of marsh plant consumer
2.4 Obesity – an evolutionary perspective If you were now to take a broader biological approach to the data discussed in the previous section you might still be puzzled. Excess body weight leads to a variety of diseases, including diabetes, osteoarthritis and so on – surely this must reduce overall biological fitness. 1.7 Summary of Section 1.2 There is a need for a certain level of daily energy intake to allow the body to maintain its BMR, and to carry out work. Adenosine triphosphate (ATP) is the chemical currency of energy used by the body and is produced from the metabolism of food. The body mass index or BMI indicates whether an adult is a healthy weight for their height. Inadequate nutrition is a huge problem globally. Anorexia nervosa is one examp Acknowledgements Grateful acknowledgement is made to the following sources for permission to reproduce material in this unit: The material acknowledged below is Proprietary and used under licence (not subject to Creative Commons Licence). See Terms and Conditions. 2.4 Summary of Section 2 The water cycle involves the movement of water, in all its forms, over, on and through the rocks near the surface of the Earth in a cycle. This cycle is driven by the Sun's energy and the Earth's gravity. The total volume of water in the cycle is virtually co 9 Glossary Click on the link below to open the unit glossary. 8 Summary Energy is the basis of modern society. Other physical resources can only be effectively extracted, processed and transported if there is a ready supply of Author(s): 7 Renewable and non-renewable energy supplies Energy resources can be considered in a completely different way from their energy density — 6 Concentrating, storing and transporting energy The Earth is awash with energy from sources other than fossil fuels; thousands of times as much a 5 Nuclear energy Einstein's famous equation E = mc2 shows that mass (m) and energy (E) are proportional to one another. The constant c2 linking the two is the square of the speed of light c (3 × 108 m s−1). Implicit in the equat 4.5 Generating carbon — the legacy of volcanoes What is the origin of the carbon within the carbon cycle? Figure 1.9 showed that the great
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