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981.
In many cities in developing countries, hunger and malnutrition are common amongst the poor, even when food is relatively abundant. Over the past two decades, a considerable literature has accumulated on the problems associated with rapid urbanization in developing countries – a literature that for the most part has neglected the important dimension of urban food systems and how these link production and consumption networks at local, regional and global levels. Similarly, whilst there is a newly burgeoning literature on global food systems, the contextual role of the urbanization process is rarely addressed. This paper attempts to fuse these two major areas of geographical investigation to highlight the issues that need to be addressed in future research programmes so that improved diets become accessible to all urban dwellers.  相似文献   
982.
Michael J. Hogan, ed., Hiroshima in History and Memory.
Edward T. Linenthal and Tom engelhardt, eds., History wars: The Enola Gay and Other Battles for the American Post.  相似文献   
983.
ABSTRACT. A general axiomatic framework is developed for analyzing alternative measures of interactivity between the sectors of a given activity system (such as the industrial sectors of an economy). Within this overall framework, we analyze an ordinal class of additive-ratio measures which has been applied to a wide variety of systems, including both economic and ecological systems of activities. Our main result is to show that such measures can be characterized by four interactivity axioms. In addition, a wide variety of alternative measures are compared to additive-ratio measures in terms of this axiom system.  相似文献   
984.
985.
986.
987.
In order to assess the effect of nutrition on bone mass, radiographs of metopodia from skeletal collections of Soay sheep (Ovis aries) were taken of animals subject to seasonal stress (from the island of Hirta, Hebrides) and those living in good nutritional conditions (from the Institute of Animal Physiology, Babraham, Cambridge). A third set of radiographs was taken at 3 month intervals over a single year on living Soay sheep kept under good conditions at the Rowett Research Institute, Aberdeen.Measurements were taken on the radiographs of length, minimum shaft width (SW) and medullary cavity width (MCW), while combined cortical thickness (CCT) was calculated. The ewes from Hirta had significantly lower values for CCT than those from Babraham, whereas the rams showed no significant reduction in CCT. Since no seasonal variation in CCT was detected in the well nourished Rowett ewes, this indicates a differential effect of poor environmental conditions on bone metabolism in ewes. It is proposed here that this may be related to the additional stress imposed by gestation and lactation on female animals living under conditions of seasonally restricted food supply.  相似文献   
988.
Reviews     
Australian

Don Aitkin, Brian Jinks and John Warhurst (eds), Australian Political Institutions, 4th edn, Melbourne, Longman Cheshire, 1989. $4.99 (paper)

F. G. Castles, Australian Public Policy and Economic Vulnerability, Sydney, Allen and Unwin, 1988, pp. 184. $19.95 (paper)

Ian C. Marsh (ed.) Australia Can Compete, Melbourne Longman Cheshire, 1988, pp. 261. $19.95 (paper)

Glyn Davis, Breaking up the ABC, Sydney, Allen & Unwin, 1988 pp. 150. $14.95. (paper)

Evatt Research Centre, State of Siege: Renewal or Privatisation for Australian Public Services?, Lei‐chardt, NSW, Pluto Press, 1989. pp. 496. $29.95 (paper)

Keith Hancock (ed.), Australian Society, Cambridge, Cambridge University Press, 1989. pp. 258. $25.00 (paper)

J. B. Hirst, The Strange Birth of Colonial Democracy. Sydney, Allen and Unwin, 1988. pp. 305. $19.95 (paper)

Keith McConnochie, David Hollinsworth and Jan Pettman, Race and Racism in Australia, Social Science Press, Wentworth Falls, NSW, 1988. pp.259. $19.95 (paper).

Martin Painter, Steering the Modern State: Changes in Central Co‐ordination in Three Australian State Governments, Sydney, Sydney University Press, 1987. pp.208. $25.00 (paper)

Comparative and International

John E. Chubb and Paul E. Peterson (eds), Can the Government Govern!, Washington D.G, Brook‐ings, 1989. pp.339. US$29.95 (paper)

Timothy E. Cook, Making Laws and Making News: Media Strategies in the U.S. House of Representatives, Washington D.C, Brookings, 1989. pp.210. US$26.95 (cloth)

Richard Crockatt and Steve Smith (eds) The Cold War Past and Present, Winchester, MA., Unwin Hyman, 1987. pp.272. US$14.95 (paper)

Leon Gordenker, Refugees in International Politics, New York, Columbia University Press, 1987. pp. 227. US$30.00 (cloth)

Stephen Hess, Organizing the Presidency, 2nd edn, Washington, D.C., Brookings, 1988. pp.273. US$10.95 (paper)

Eric Hobsbawm, Politics for a Rational Left, London, Verso, 1989. pp. 250. £8.95 (paper)

Robert A. Katzmann (ed.), Judges and Legislators: Towards Institutional Comity, Washington, Brookings, 1988. pp. 200. US$10.95 (paper)

Fred Krinsky (ed.), Crisis and Innovation: Constitutional Democracy in America, Oxford, Basil Blackwell, 1988. pp.158. $34.95 (paper)

Philip Laundy, Parliaments in the Modem World, Aldershot, Gower, 1989. pp.166. £25.00 (doth)

Stanley Bach and Steven S. Smith, Managing Uncertainty in the House of Representatives: Adaptation and Innovation in Special Rules, Washington D.C., Brookings, 1988. pp. 140. US$22.95 (cloth)

Timothy Mitchell, Colonising Egypt, Cambridge, Cambridge University Press, 1988. pp.218. US$42.50 (cloth)

Carol M. Mueller (ed.) The Politics of the Gender Gap: The Social Construction of Political Influence. Newsbury Park, California, Sage, 1988. pp.316. US$ 16.95 (paper)

John Newhouse, The Nuclear Age: From Hiroshima to Star Wars, London, Michael Joseph, 1989. pp.486. £15.95 (cloth)

Richard Rose, Ordinary People in Public Policy. Newbury Park, California, Sage, 1989. pp.189. US$8.95 (paper)

Richard Rose, The Postmodern President: The White House Meets the World, Chatham, New Jersey, Chatham House, 1988. pp. 349. US$14.95 (paper)

William E. Rosenbach and Robert L. Taylor (eds) Contemporary Issues in Leadership, 2nd edn, Boulder, Westview, 1989. pp.248. US$16.95 (paper)

Angus Mclntyre (ed.) Aging and Political Leadership, Melbourne, Oxford University Press, 1988. pp. 316. $35.00 (cloth)

Graham Little Strong Leadership: Thatcher, Reagan and An Eminent Person, Melbourne, Oxford University Press, 1988. pp. 289. $ 19.95 (paper)

Emile Sahliyeh, In Search of Leadership: West Bank Politics Since 1967, Washington, D.C., Brookings, 1988. pp. 201. US$10.95 (paper)

Betty H. Zisk, Money, Media and the Grass Roots: State Ballot Issues and the Electoral Process. New‐bury Park, California, Sage, 1987. pp.279. US$12.95 (paper)

Political Theory and Methodology

Terrell Carver, Marx and Engels: The Intellectual Relationship. Harvester Press, Sussex, 1983. pp. 172. $50.00 (cloth)

Levi, Margaret, Of Rule and Revenue, Berkeley, University of California Press, 1988. pp.253. US$10.95 (paper)

Robert Paul Wolff, Understanding Marx: A Reconstruction and Critique of Capital, New Jersey, Princeton University Press, 1984. pp.235. US$8.95 (paper)  相似文献   

989.
Despite a limited number of notable exceptions, children's geographers are not generally engaged with the policy process. Drawing on research carried out for the UK's Department for Education and Skills, this paper will argue that children's geographers are ideally placed to explore a number of important research questions appertaining to the impact of policy reform on children's lives. It suggests that by actively engaging with the policy process, we, as children's geographers, can bring a fresh and important perspective to the policy arena.  相似文献   
990.
Quantifying Interpolation Errors in Urban Airborne Laser Scanning Models   总被引:1,自引:0,他引:1  
Airborne laser scanning (ALS) is becoming an increasingly popular data capture technique for a variety of applications in urban surface modeling. Raw ALS data are captured and supplied as a 3D point cloud. Many applications require that these data are interpolated onto a regular grid in order that they may be processed. In this article, we identify and analyze the magnitudes and spatial patterning of residuals from ALS models of urban surfaces, at a range of different scales. Previous research has demonstrated the effects of interpolation method and scale upon the nature of error in digital surface models (DSMs), but the size and spatial patterning of such errors have not hitherto been investigated for urban surfaces. The contribution of this analysis is thus to investigate the ways in which different methods may introduce error, and to understand the uncertainty that characterizes urban surface models that are devised for a wide range of applications. The importance of the research is shown using examples of how the different methods may introduce different amounts of error and how the uncertainty information may benefit users of ALS height models. Our analysis uses a range of validation techniques, including split-sample, cross-validation, and jackknifing, to estimate the error created in DSMs of urban areas.  相似文献   
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