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101.
Fifty-three copper-based metal fragments, recovered from the Robitaille site in southcentral Ontario, were analysed by neutron activation to establish their chemical make-up and to sort them by their trace elemental chemistries. Three different European copper samples, one brassy copper and 48 brass samples with five different chemistries were found. As few as eight trading actions may account for all of the recovered European metal fragments. 相似文献
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Reed JW 《Journal of policy history : JPH》1995,7(1):22-52
This essay synthesizes the history of the birth control movement in the US and describes changes in sexual behavior, social values, and public policy in order to provide a context for the changes in human reproductive public policy. After an introduction, the essay outlines the history of contraception from the early nineteenth to the early twentieth centuries. Part 3 covers the period of World War I to the Depression when civil libertarians and eugenicists began to question the suppression of contraception and Margaret Sanger organized her clinics. The fourth part of the essay carries the history forward to the end of World War II, a period in which Dr. Clarence J. Gamble began to expose the marketing of defective contraceptive methods and to illustrate the willingness of poor women to accept contraceptives. The social changes which began in the 1950s are the subject of the fifth section of the essay. During this period, Roman Catholic opposition to contraception lessened, and social scientists began to focus world attention on overpopulation. Frank Notestein was appointed the first head of the Office of Population Research at Princeton, and John D. Rockefeller III founded the Population Council which conducted research into the IUD and began to attempt to influence population growth in nonindustrialized countries. This period also saw the development of the oral contraceptive. The changes of this era were institutionalized in 1967 when the federal government took a positive stance towards family planning in its Social Security Amendments. The decade of the 1970s is the subject of the last part of this essay. This period saw the Supreme Court assign a constitutionally protected right to abortion and Congress pass the Helms Amendment which denied the use of foreign aid funds for abortions. Challenges to the right to individual birth control practice continued during this period, and debate centered around the specter of overpopulation, the threat of adolescent pregnancy, and perceptions of "family values." 相似文献
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Morphological Impacts and Implications of a Trial Release on the Wingecarribee River,New South Wales
A trial, monitored release on the Wingecarribee River over 27 days had a peak discharge below the Wingecarribee Dam of 1090 ML/d, which had a flow duration of 0.95 per cent. Morphological impacts on 29 km of channel below the dam included bank erosion, concentrated neck overflow, bed degradation and channel widening at recent cutoffs, sedimentation in weir pools and overbank flow, particularly at discharges greater than 800 ML/d. Prolonged operational releases at bankfull discharge (400–800 ML/d) will have the greatest morphologic impacts and should be avoided. Pulses which dissipate stream power over a broad, well-vegetated floodplain should be incorporated in the operational release policy, provided such pulses are phased to facilitate channel and vegetation recovery. 相似文献
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C. F. W. Higham 《International Journal of Historical Archaeology》1998,2(3):235-260
The Early Historic Period in the Mun Valley occupies a critical three centuries, from A.D. 500 to A.D. 800, a period often known as that of Zhenla, a name derived from early Chinese accounts. This article first describes early findings of fieldwork designed to illuminate the prehistory of the upper Mun Valley, a period which covers approximately two millennia, with initial settlement now dated between 1500 and 1000 B.C. It then considers the nature of the transition to the complex polities of Zhenla. This involves a combination of archaeological and documentary evidence. Sources for the latter are rare for the Mun Valley, but by broadening the area considered, it is possible to integrate archaeological and historical sources in order to portray the intensifying social changes which characterize the Early Historic Period. It is suggested that most of the Mun Valley was occupied by Khmer speakers during the Iron Age, people responsible for the transition to increasingly centralized polities of the Early Historic Period. In the upper reaches of the Mun catchment, and in the Chi Valley to the north, the late prehistoric inhabitants spoke Mon. They had close affinities with the Dvaravati polities of Central Thailand. If confirmed, this hypothesis would indicate a series of local trends towards increasing social complexity which we can recognize in the early epigraphic record. 相似文献