Proton propagation in nuclei was studied using the (e,elp ) reaction in the quasifree region. The coincidence (e,elp) cross sections were measured at an electron angle of 50.4" and proton angles of 50. lo, 58.2", 67.9", and 72.9" for I2C, "~1 , 58Ni, and I8'Ta targets at a beam energy of 779.5 MeV. The average outgoing proton energy was 180 MeV. The ratio of the ( e , e l p ) yield to the simultaneously measured (e, e') yield was compared to that calculated in the plane-wave impulse approximation and an experimental transmission defined. These experimental transmissions are considerably larger (a factor of -2 for 1 8 '~a ) than those one would calculate from the free N-N cross sections folded into the nuclear density distribution. A new calculation that includes medium effects (N-N correlations, density dependence of the N-N cross sections and Pauli suppression) accounts for this increase.

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The dynamics of community, place, and identity Introduction The aim of this theme issue is to explore the concept of community in the light of a number of important theoretical trends within the academy, and the upsurge in popularity of 'big themes' based upon it in North American and UK politics. I will make no attempt to provide a comprehensive treatment of community in terms either of breadth of theory or of range of empirical studies. However, the five papers that follow this introductory essay provide excellent examples of the different directions in which contemporary studies of community can lead.There are several areas of theoretical development that I find particularly promising and interesting.The first is politicomoral and is centred on a debate between liberals and communitarians. One sphere of this debate is in political and moral philosophy; the other revolves around 'popular communitarianism' whose advocates have the ear of politicians. In each liberals and communitarians are often at odds, and both are subject to feminist critiques. Much discussion here is focused on the extent to which community is, or should be, a moral force. Another important relationship, too often neglected, is that between community and the subject position of citizen.The second area of development owes much to new conceptions of relations between place and space influenced by poststructuralism and recent work on globalisation which, I will argue, have been exemplified by the sociospatial relations of community for some time.Another strand consists of theoretical work in which community is dealt with in terms of collective identity and collective action, and in which account is taken both of instrumental and of communicative rationality. The notion of purposive and instrumental community action is an important one that can be neglected, given the 'cultural turn' in geography and the tendency to give priority to discursive-symbolic factors.Fourth, there is work in which the constructed and contested nature of community in the context of power relations and 'difference' is stressed. Strongly influenced by poststructuralism, this work has a 'mongrel' pedigree which includes political economy and the politics of identity. CommunitarianismThere is a broad distinction between the high theory of philosophical communitarianism, and its popular appropriations which have direct policy implications. The high theoreticians focus more on the difference between the atomised individual and the relational self; and the popularisers upon the relative importance of individual rights and community obligations, although there is considerable crossover. Here I provide the broadest outline of this terrain, recognising that the terms 'liberalism' and 'communitarianism' mean different things to different people-for a comprehensive review see Arthur and Shaw (1991) or Mulhall and Swift (1992). There are also important feminist critiques which Smith considers in his paper in this issue.In a paradigmatic statement of the liberal position, Rawls (197...

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