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Investigators have long recognised the effects of microbial activity on archaeological bone. These investigators, however, have focused on single or groups of microbes rather than on complex microbial aggregates such as biofilms, a focus that has affected our understanding of archaeological bone biodeterioration. In this paper, we report on the investigation of a biofilm in archaeological human bone from the site of Tell Leilan, Syria (2900–1900 BCE). Scanning electron microscopy indicated that the biofilm is characterised by single cells and microcolonies of bacteria and fungi, as well as calcite crystals that were all embedded within extracellular polymeric substances. Using culture techniques and DNA sequencing, we isolated and identified several microbes from the biofilm including Amycolatopsis sp., Penicillium chrysogenum, Aspergillus sp., Chaetomium sp., and Cladosporium sp. Having characterised the Leilan biofilm, we are now closer to understanding the complex process of bone biodeterioration in archaeological bone collections.  相似文献   
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Book Reviews     
George, Alexander L., and Juliette L. George. Presidential Personality and Performance. Boulder, CO: Westview Press, 1998. Pp. x, 304. $75.00, hardbound; $25.00, softbound.

Epstein, David, and Sharyn O'Halloran. Delegating Powers: A Transaction Cost Politics Approach to Policy Making Under Separate Powers. New York: Cambridge University Press, 1999. Pp. xvi, 320. $59.95, hardbound; $19.95, softbound.

Kahn, Kim Fridkin, and Patrick J. Kenney. The Spectacle of U.S. Senate Campaigns. Princeton, NJ: Princeton University Press, 1999. Pp. xiv, 278. $57.50, hardbound; $18.95, softbound.

Michaels, Judith E. 1997. The President's Call: Executive Leadership from FDR to George Bush. Pittsburgh: University of Pittsburgh Press. Pp. x, 348. $50.00, hardbound; $22.95, softbound.

Savage, James D. Funding Science in America: Congress, Universities, and the Politics of the Academic Pork Barrel. New York, Cambridge University Press, 1999. Pp. xiii, 219. $49.95, hardbound.

Stid, Daniel D. The President as Statesman: Woodrow Wilson and the Constitution. Lawrence, KS: University of Kansas Press, 1998. Pp. xi, 231. $35.00, hardbound.

Steven Shull. American Civil Rights Policy from Truman to Clinton: The Role of Presidential Leadership. Armonk, New York: M.E. Sharpe, 1999. Pp. xv, 294. $64.95, hardbound.

Yalof, David Alistair. Pursuit of Justices: Presidential Politics and the Selection of Supreme Court Nominees. Chicago: University of Chicago Press, 1999. Pp. x, 296. $27.95, hardbound.  相似文献   
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This study tests the neoclassical concept of interregional migration in post–World War II Japan. The lead-lag relationship between net migration to a core area and regional income inequalities is examined by modeling an ARIMA transfer function. Until 1961, there was a rapid growth in net migration from the periphery to the core area that was accompanied by rapid divergence in regional income inequalities. Since then, migration to the core apparently has declined due to a convergence of regional income inequalities. The time series analysis indicates there has been short-run, as well as long-run, volatility in migration related to cyclical variations in economic performance in the core.  相似文献   
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Land speculation played a major role in the settlement of Ontario. Its impact has been discussed in great detail but there always remained the problem of identifying individual speculators. Previous studies have identified land speculators solely on the basis of the amount of land held. This paper presents an alternative method of identifying speculators by calling attention to the motivations behind speculation and manifestations of these motivations as inferred in landholding behaviour. In addition, a typology of speculators is presented. Elizabethtown Township provides the setting for an application of the proposed method and a brief analysis of the speculative patterns that emerge.
Les achats speculatifs des terrains, ayant joué un rôle majeur dans la colonisation de l'Ontario, ont souvent été examinés en détail: le probléme de l'identité des speculateurs est pourtant resté sans solution. Dans des études déjà parues, ceux-ci ont été discernés en ne tenant compte que de la superficie des terrains qu'ils detenaient. Cet essai presente une autre méthode pour identifier les spéculateurs en examinant les mobiles de la spéculation tels qu'ils sont révéles par la conduite de Tacheteur: nous avons aussi formulé une typologie des spéculateurs. Nous avons appliqué la méthode proposée à la ville d'Elizabethtown pour analyser brièvement les mouvements spéculatifs qui s'y présentent.  相似文献   
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This article considers theories of collective action in relation to the management of communal water resources in Nkayi District, Zimbabwe. Taking a critical view of institutional explanations of common property resource management, it illustrates how the addition of social theory can enrich such approaches. The prevalence of rational choice premises in defining the problem of collective action and the persuasiveness of institutionalism in apparently offering solutions to it is questioned. The article rejects simple evolutionary theorizing about institutions in favour of an embedded approach that allows for complexity, for the social and historical location of collective action and for an examination of the interface between agent and structure. It is argued here that collective management of water supplies does exist but that it is more partial, changeable and evolving and less attributable to single factors than suggested in much of the literature.  相似文献   
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This article analyses ethnic nationalism and liberalism as expressed in the views of Croatians in the aftermath of the 1991–5 war – a war during which ethnic-nationalist rhetoric played a large role. Because the war was part of systemic change in the nation, including the adoption of more democratic and capitalist social formation, we also anticipated economic and political liberalism to be present among a sizeable portion of the population. We provide an analysis of the structural conditions fostering these sentiments, an analysis potentially applicable to a range of societies presently in transition. Based on 1996 survey interviews (N=2,202) conducted throughout Croatia, we show that ethnic nationalism in the Croatian context is more widely shared than is liberalism. The effect of religious fundamentalism, educational attainment and media exposure are as predicted, based on theories of liberalism and nationalism. Wartime experiences and position in the occupational system have a weaker and more mixed influence than hypothesised. Perhaps most importantly, we find that three out of five Croatians embrace both ethnic-national views and views that are distinctly liberal, suggesting that liberal nationalism is now dominant in Croatia. The characteristics of groups holding differing views suggest that recent events and current changes in Croatia bode positively for continued growth of liberal sentiments, but this will not necessarily be at the expense of ethnic nationalism.  相似文献   
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