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101.
A chronic feature of Caribbean agriculture is the extent to which potential arable land lies idle. Some of this region's densely populated islands have more than one-third of their farmland in such a condition. Yet their populations have relied increasingly upon imported food for sustenance. During the 1970s this paradoxical situation was exemplified by Grenada, where possibly as much as 45 per cent of its farmland lay abandoned and imported food accounted for one-third of the national import bill. This paper first surveys the underlying factors accounting for idle land in this nation and then outlines the programs pursued by the People's Revolutionary Government (PRG) to reduce waste of this basic resource and, thereby, to effect a more stable economy.
Dans la scène agraire caraibe on trouve constamment des terres dormantes qui pourraient ětre cultivées. Quelques les, des plus fortement peuplées de la région, ont plus du tiers de leurs terres ambles dans une telle condition. Toutefois, leurs habitants se fient de plus en plus sur la nourriture importée pour se soutenir. Cette situation paradoxale s'illustre par la Grenade, des années soixante-dix, où jusqu'a 45 pour-cent du terroir aurait été abandonné, en méme que la nourriture importée se payait du tiers du budget disponible pour défrayer toutes les importations requises dans ľle. Cette communication souligne ďabord les facteurs qui ont Créé cette situation en Grenade, et présente ensuite les grandes lignes des programmes adoptés, par le gouvernement révolutionnaire du peuple, pour couiger cette situation et pour diriger ľle vers une économie plus stable qu'au paravant.  相似文献   
102.
Discovery of the uses and later the invention of fire-making are fundamental to humanity. Following reports over the last decade of traces of fire found on Lower Pleistocene archaeological sites in eastern Africa, the dating of the control of fire by hominids has become a controversial issue. In this paper we critically review the contexts and, in the light of a battery of archaeometric techniques, the nature of reported instances of fire from Koobi Fora and Chesowanja in Kenya, and from Gadeb and the Middle Awash in Ethiopia. We conclude with a discussion of the roles fire may have played in the lifeways of early Pleistocene savanna-living hominids.
Résumé La découverte des usages du feu et ensuite de sa préparation est fondamentale pour l'humanité. Suite à des rapports au cours de la dernière décennie signalant des traces de feu relevées dans des sites archéologiques du Pléistocène inférieur dans l'est de l'Afrique, la datation du contrôle du feu par les hominiens est devenu une source de controverse. Dans cet article, nous révisons d'un oeil critique les contextes et la nature des cas de feu signalés à Koobi Fora et à Chesowanja au Kenya, et à Gadeb et dans l'Awash moyen en Éthiopie, à la lumière d'une suite de techniques archéometriques. Suit en conclusion une discussion sur les rôles qu'aurait pu jouer le feu dans les modes de vie des hominiens vivant dans les savannes du Pléistocène inférieur.
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Nearshore water circulation and bar patterns at Coledale, New South Wales, were surveyed daily over thirty-six consecutive days, from 3 November to 8 December 1978, to identify sequences of changes that might occur in response to spring-to-spring tide cycles of fourteen days, changing barometric and wind conditions associated with the passage of anticyclonic weather systems across the coast, and day to day variation in the nearshore wave regime. During the survey the bar patterns tended to vary from transverse bars, through a composite arrangement incorporating longshore and transverse bars, to a longshore bar pattern as the tide changed from its spring to neap tide phase. However, this sequence was too brief to unequivocally establish variations in nearshore bar pattern that might be attributed to the fourteen day, spring-to-spring tide cycle. Nevertheless, morphologic changes occurring in response to wave regime fluctuation at Coledale were broadly in accord with studies from elsewhere by Dolan et al. (1979, 1982), and Clarke and Eliot (1982, 1983) in that bars and rips were systematically distributed along the beach. At Coledale, bars tended to relocate approximately 0.4 and 0.75 of the distance along the beach from its southern end. The preferred bar spacing closely matches hypothetical standing waves trapped between the headlands of the Coledale embayment. Temporally, the nearshore morphology is highly responsive to wave regime changes such that, as primary breaker heights decrease and remain below Hmax=1.0m, the bar pattern changes from longshore through mixed to transverse bar patterns within three to five days. On one occasion the bar pattern switched from a longshore to a transverse bar pattern within twenty-four hours.  相似文献   
106.
The Multiregional Variable Input-Output (MRVIO) model is introduced to measure the development impact of a transportation system. The MRVIO model is a theoretically flexible, computationally simple, and cost-responsive model. Under the MRVIO model, regional input-output coefficients, trade coefficients, and trade flows become cost responsive and easy to compute. The MRVIO model is employed to measure the development impact of the Arkansas waterway during the period of 1974 to 1978. In the study, the U.S. economy is disaggregated into 3 regions and 35 industrial sectors. The MRVIO model estimates the economic conditions of these 3 regions with and without the waterway in terms of industrial output, income, employment, and trade flows.  相似文献   
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Book reviews     
Derek McDougall, Harold D. Lasswell and the Study of International Relations. University Press of America, Lanham, USA, 1984, pp.370. $16.50.

John W. Burton, Global Conflict: The Domestic Sources of International Crisis. Wheatsheaf Books, UK, 1984, pp.194. $54.00.

K.J. Holsti, The Dividing Discipline: Hegemony and Diversity in International Theory. Allen and Unwin, Boston and Sydney, 1985. pp.165. $39.95.

Hedley Bull (ed.), Intervention in World Politics. Clarendon Press, Oxford, 1984, pp. viii + 198. $31.00.

Hedley Bull, Justice in International Relations. 1983–84 Hagey Lectures, University of Waterloo, 1984, pp. iii + 36. No price given. (Available from University Publications Distribution Service, Dana Porter Arts Library, University of Waterloo, Waterloo, Ontario N2L3G1, Canada.)

Benedict Anderson, Imagined Communities: Reflections on the Origin and Spread of Nationalism. Verso Editions and NLB, London, 1983, pp. 160. £15.00.

Chalmers Johnson, Revolutionary Change. Second edition. Longman, London, 1983, pp.xii + 217. $13.85.

Peter Calvert, Politics, Power and Revolution. An Introduction to Comparative Politics. Wheatsheaf Books, Brighton, 1983, pp.208. £5.95.

John Walton, Reluctant Rebels. Comparative Studies of Revolution and Underdevelopment. Columbia University Press, New York, 1984, pp.xii + 230 $US36.00 (cloth), $US10.00 (paper).

E. A. Tiryakian and R. Rogowski (eds), New Nationalisms of the Developed West. Toward Explanation. Allen and Unwin, Boston, 1985, pp.xii + 394. $69.00.

Peter H. Merkl and Ninian Smart (eds), Religion and Politics in the Modern World. New York University Press, New York, 1985, pp.276. No price given.

Richard Lowenthal, Social Change and Cultural Crisis. Columbia University Press, New York, 1984, pp.viii + 252. $US29.50.

Dietrich Fischer, Preventing War in the Nuclear Age. Rowman and Allanheld, Totowa, N.J./Croom Helm, London, 1984, pp. x + 236. $27.95.

F. Dyson, Weapons and Hope Harper and Row, New York, 1984, pp.340. $24.95.

John Langmore and David Peetz (eds), Wealth, Poverty and Survival. Australia in the World. George Allen and Unwin, Sydney, in association with the Australian Labor Party, 1983, pp. 225.  相似文献   

110.
ABSTRACT. The intertemporal structure of regional nominal-wage differentials by race is estimated using panel data from 1973 through 1978. This allows for a more complete analysis of the time pattern of changes in wage differentials, which is not possible from cross-sectional studies. The findings indicate that, in addition to the presence of substantial locational differentials, there was a systematic change in the differentials over time.  相似文献   
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