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81.
82.
During the archaeobotanical investigation of Scythian–Sarmatian period (Early Iron Age), pits with crop processing waste, discovered in the floodplain of Donets River, eastern Ukraine, and charred remains of cereal grains, dominated by broomcorn millet, were recorded. The grains from the pits were radiocarbon dated to the fifth to first century BC. Those pits are distant from any known contemporaneous settlement. The apparent disconnection of these pits from any local settlement suggests that (1) millet was brought from other locations by mobile groups, or (2) millet was cultivated locally by populations whose settlements have left no discernible archaeological trace. The analysis of molecular biomarkers preserved in palaeosols that are stratigraphically connected to the pits revealed high levels of miliacin, a molecule that can be preserved in ancient soils and sediments, and that is consistent with broomcorn millet (Panicum miliaceum). High levels in miliacin in soils stratigraphically connected to the pits are interpreted as the result of a large biomass of P. miliaceum produced at time of soil formation. Our biogeochemical results applied to a palaeosol thus attest to the in situ cultivation of crops dominated by the broomcorn millet during the early Iron Age in the floodplain of Donets River. Biochemical examination of soils and palaeosols can thus provide useful information on past dynamics of land-use by ancient population, especially when settlements or macrobotanical remains are absent.  相似文献   
83.
Observations are presented of a newly deposited snow-push ridge superimposed on a Holocene moraine in Coire an Lochain in the Cairngorm Mountains. The ridge formed when a sliding snow slab was thrust up the proximal slope of the moraine, entraining till gravel and redepositing it on the moraine crest. The process was a late-stage event during the complex wastage of a large snowfield resting on a rock slab, involving basal sliding, avalanching and melting. Snow-push landforms appear to be rare in Scotland. Nevertheless, these observations suggest that fresh material may be added to relict moraine crests in the present-day climate, with implications for exposure-age dating of moraines. However, in this case the addition of debris by snow push to a late Holocene moraine crest does not affect the interpretation of moraine age.  相似文献   
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Several attempts have been made recently to apply Darwinian evolutionary theory to the study of culture change and social history. The essential elements in such a theory are that variations occur in a population, and that a process of selective retention operates during their replication and transmission. Location of such variable "units" in the semantic structure of cognition provides the individual psychological basis for an evolutionary theory of history. Selection operates on both the level of cognition and on its "phenotypic" expression in action in relation to individual preferred sources of psychological satisfaction. Social power comprises the principal selective forces within the sociocultural environment. Sociocultural evolution takes place both as a result of the unintended consequences of action and through the struggle of individuals and groups in pursuit of opposing interests. The implications for historiography are methodological in that evolutionary theory of history sharpens the focus of explanatory situational analysis, and interpretive in that it provides a paradigmatic metanarrative for the understanding of historical change.  相似文献   
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The introduction of Western science in order to change physical and operational aspects of Shanghai’s Huangpu River had been debated by Qing and Western officials since almost the beginning of its history as a Treaty Port. At stake in those debates was the perception of the river’s proper use: as a natural barrier for military defense, or as a conduit for global trade. After the Western powers unified to militarily suppress the Boxer Uprising in 1900, they attained their long-awaited goal of the right to transform the river for global trade as part of Article 11 of the Boxer Protocol: the Junpuju (or Huangpu Conservancy Board) was created and authorized by the central government to make the Huangpu River navigable for shipping vessels. Although the Junpuju continued the ethos of earlier extra-bureaucratic organizations established during the Self-Strengthening Movement, after 1901 the organization bore the authority of the central government. During the era of the New Policies, Qing officials were intent on revising the original terms of river conservancy so that they would be more favorable to Chinese sovereignty. At the same time, imperialist rivalries among the Western powers ruptured the apparent unity of the earlier alliance during the suppression of the Boxer Uprising. Before long, Western corruption in the Huangpu River dredging was brought to the attention of Qing officials, who deftly used it to recover Qing control over certain parts of the body of the river.  相似文献   
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This essay examines a crucial period in New Zealand Baptist life. During the 1940s Baptist leaders sought to establish a more centrally organised denomination than had previously existed. Motivated by a desire to position Baptists closer to the mainstream of Protestant religious life, this centripetal dynamic was tested by a cluster of crises and debates. Some of these reflected theological tensions that had been present in the denomination for decades. Others, more immediate and linked to particular personalities, exposed key issues of control and authority. The leadership of the largest church, Baptist involvement in the Ecumenical movement, and the principalship of the theological college were contested. Despite the considerable potential for division, the outcome was a more connectional denomination, able to maintain unity under stress, though one not as centrally driven as some in the Executive desired.  相似文献   
90.
In recent years, Head Start's prominent role in preparing low‐income 4‐year‐olds for school has been affected by rapid growth in state‐funded pre‐K programs, some of which are based in public schools. This has led to questions about the comparative advantages of these two approaches to early education. An analysis of data from Tulsa, Oklahoma, indicates that the school‐based pre‐K program is more effective in improving early literacy outcomes, while Head Start is more effective in improving health outcomes. The two programs are comparable with regard to early math learning. Social–emotional effects are more subtle, but the school‐based pre‐K program has demonstrable positive effects, while the Head Start program does not.  相似文献   
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