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941.
The biggest problem with most lakes that have no contact with other water sources and are being charged by precipitation is the massive eutrophication. The aim of this work was to determine the sedimentation rate in order to evaluate the progress of eutrophication for St. Ana Lake (Ciomad Mountain near the Băile Tuşnad in Harghita County (Romania)). The concentration of 210Pb was determined by means of high resolution gamma spectrometry as well as derived from 210Po activity which was measured through alpha spectrometry; values obtained are in good agreement. For the excess 210Pb activity values between 4.0±0.5 Bq/kg and 218±20 Bq/kg have been found. As an alternative method, the 137Cs dating method was applied as well. Calculated mass sedimentation rates are in the range of 0.06±0.01 to 0.32±0.05 g/cm2 year with a mean of value of 0.15±0.02 g/cm2 year. Linear sedimentation rates yielded much higher sedimentation values (between 0.5±0.1 and 7.9±0.7 cm/year with a mean of 2.4±0.6 cm/year), due to the predominant organic matter composition and the long suspension time of the sediment. This is an indication for the process of eutrophication which will probably lead to the transformation of the lake into a peat bog.  相似文献   
942.
In the course of the 9th century areas in Western Europe were conquered by the Vikings. The Isles of Orkney were settled by Norwegians and became a stronghold. Some possible economic characteristics of Orkney have been considered in an attempt to gain insight into how the local resources might have: been exploited and into the contact between Norway‐Orkney and The British Isles.  相似文献   
943.
944.
John Vail  Robert Hollands 《对极》2013,45(3):541-564
Abstract: This article explores the various forms of “social skill”, what we call “rules for cultural radicals”, that the Amber Film and Photography Collective (and primarily its founder and leading visionary, Murray Martin) used to create and sustain an egalitarian arts organization and oppositional cultural movement in the Northeast of England. The collective represented a radical challenge to the world of British filmmaking, featuring innovative practices of cultural work, non‐commodified forms of cultural economy and a commitment to a democratic culture. These “rules” constituted innovative forms of strategic action—visionary leadership, improvisation, risk taking, brokerage—that helped create a durable collective identity and networks of solidarity. We explore the extent to which Amber's “rules” are prefigurative of contemporary forms of cultural activism and radical artistic practice.  相似文献   
945.
Abstract

Recent scholarship has called attention to the common features shared by five French and British elite centres of leisure called ‘gloriette’ that were built or so-named in the late 13th and early 14th centuries. Because these centres of repose and entertainment were located in principal residences, and thus were not garden pavilions, it has been suggested that there was no relationship between the northern gloriettes and the garden pavilion of La Zisa in Palermo, Sicily, whose name also meant ‘the glorious’. This article draws on archival sources in order to enhance our understanding of the resemblances between the gloriette of Hesdin, in northern France, and the four gloriettes in England and Wales. Drawing on the significant features of these five northern gloriettes, it also takes another look at the details of La Zisa, suggesting that we should not be so quick to dismiss its possible influence on the northern gloriettes, most especially the two that were built by King Edward I and Count Robert II of Artois after they had passed through Palermo in 1270/72.  相似文献   
946.
Carl Heine. Micronesia at the Crossroads: A Reappraisal of the Micronesian Political Dilemma. Honolulu: The University Press of Hawaii, 1974. xvi + 210 pp. Notes, appendices, bibliography, and index. $10.00 (cloth); $2.95 (paper).

Daniel T. Hughes and Sherwood G. Lingenfelter, eds. Political Development in Micronesia. Columbus: Ohio State University Press, 1974. 333 pp. Tables, charts, references, and index. $15.00.  相似文献   
947.
Jerrold E. Levy and Stephen J. Kunitz. Indian Drinking: Navajo Practices and Anglo‐American Theories. New York: John Wiley & Sons, 1974. xii + 257 pp. Tables, notes, appendices, bibliography, and index. $12.50.

William Madsen. The American Alcoholic: The Nature‐Nurture Controversy in Alcoholic Research and Therapy. Springfield: Charles C. Thomas, 1974. xvii + 248 pp. References, author and subject indices. $11.50.  相似文献   
948.
949.
Abstract

Polish lands in 19th century are usually located in the economic peripheries of Europe. However there are no usable datasets of Polish GDP for this period to verify this hypothesis. The main problem is lack of reliable and comparable macroeconomic data from country divided between Russia, Austria and Prussia. The main goal of this research was to propose the method based on the urbanization data set to estimate the GDP of Polish territories and to verify the hypothesis on the peripheral development of Polish lands. In result the new estimates on GDP per capita were established, that allowed to confirm the hypothesis of semi-peripheral development of Polish territories in 19th century and slow process of catching-up with the core economies.  相似文献   
950.
Abstract

Two great movie directors were both born in 1930. One of them, Jean-Luc Godard, revolutionized filmmaking during his 30s and declined in creativity thereafter. In contrast, Clint Eastwood did not direct his first movie until he had passed the age of 40 and did not emerge as an important director until after he was 60. This dramatic difference in life cycles was not accidental, but was a characteristic example of a pattern that has been identified across the arts: Godard was a conceptual innovator who peaked early, whereas Eastwood was an experimental innovator who improved with experience. This article examines the goals, methods, and creative life cycles of Godard, Eastwood, and eight other directors who were the most important filmmakers of the second half of the twentieth century. Francis Ford Coppola, Stanley Kubrick, Stephen Spielberg, and François Truffaut join Godard in the category of conceptual young geniuses, while Woody Allen, Robert Altman, John Cassavetes, and Martin Scorsese are classed with Eastwood as experimental old masters. In an era in which conceptual innovators have dominated a number of artistic activities, the strong representation of experimental innovators among the greatest film directors is an interesting phenomenon.  相似文献   
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