The effects of pH, ionic strength, temperature, and protein concentration on the rate of clathrin (8 S) polymerization to form coat (or basket) structures (approximately 300 S) have been measured by turbidity. The extent of polymerization has also been evaluated under the same experimental conditions by analytical centrifugation. The characteristic polygonal structure of the re-formed coat was confirmed by electron microscopy. The rate of polymerization is sensitive to all the variables investigated. The reaction is very slow at pH approximately 7 and becomes very rapid by pH approximately 6. The polymerization is readily reversed by increasing the pH slightly. The time dependence of the polymerization does not conform to either a first- or a second-order reaction but to a higher order. Increasing temperature increases the rate but decreases the extent of reaction. Increasing the salt concentration decreases the rate. The effects of several salts on the rate follow the Hofmeister ranking, with the exception of sulfate.

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An interactive and incremental developmental approach to sustainable development is proposed. It requires broad public participation, is based on the development of a shared value system for civic society and norms which determine the behaviour of states. It is aimed at building commitment rather than directing change. This is achieved by simultaneoulsy harnessing the notions of 'positive human survival' adopted from Global Security theory and a co-evolutionary approach to human socio-economic constructs. Modern threats to Nation States can be regarded as 'threats without enemies', are not compatible with traditional views of sovereignty, and confronting such threats frequently requires co-operative behaviour and good neigbourliness from states. Principles likely to underpin an evolving shared value system for Nation states and civil society include: democracy, equity and diversity. In order to deal with the uncertainty of evolving socioeconomic constructs and the conceptual pluralism inherent in modern societies, public agencies need to develop significant mediation, negotiation and facilitation skills. This view has significant implications for National and Regional policy, and the democratisation of information and the development of early warning capabilities about potential threats to human security are pivotal.