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21.
自1965年以来迁入美国的外来移民日渐增多,并在20世纪末期达到了历史高潮。在入境移民中,整体学历结构呈两极化趋势:即接受1-11年教育的移民和在大学学习一年以上的移民比例相对较高,而高中毕业的移民数量较少。这种状况源于美国移民政策中强调移民家庭团聚条款,同时也因为美国在20世纪后半期吸纳了大量难民,赦免了数百万低学历的非法移民。在各民族群体中,墨西哥和拉丁美洲移民的学历整体较低,亚洲和欧洲移民的学历较高。另一方面,高学历移民呈逐渐提高的趋势,特别是在90年代更加明显,这主要归因于美国政府加大引进外国优秀人才的政策。大量优秀人才从中国等发展中国家的流失值得重视。  相似文献   
22.
In 1912, Daniel Alexander Payne Murray published a prospectus for his “Historical and Biographical Encyclopedia of the Colored Race throughout the World.” He promised to publish what literary historian Henry Louis Gates Jr., would describe as the “Grail” for black scholars. As Murray planned his encyclopedia in the first decade of the twentieth century, persons of African descent in the United States were killed and assaulted because of their race, and racial identification was as critical an issue as it was also ambiguous. Moreover, despite its ambiguity, or perhaps, because of it, race, in 1912 and since the Naturalization Act of 1790, had everything to do with American citizenship. In Murray’s time, whether a person was identified on the one hand as “white” or “octoroon” versus an identity as “black,” “Negro,” “mulatto,” or “quadroon” influenced whether or not that person could exercise his rights as an American citizen (with her rights barely entering the question). However, race, as Murray understood with its skin color codes shading the meaning of American citizenship, was much more a social construction than it was biological evidence of a person’s hereditary origins. Formulating a strategy in support of black American citizenship, Murray developed a global interpretation of the black American experience from a pragmatically ambiguous cultural practice to compose an identity for himself, his people, and his proposed encyclopedia.  相似文献   
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《Northern history》2013,50(2):27-71
Abstract

Plumpton, an ardent Lancastrian, received protection and patronage from the Percies and was loyal to them throughout his life. He enjoyed exceptional local power from 1438 to 1460 as steward of the Honour of Knaresborough. He served as a JP, an MP, sheriff, and steward of Northumberland's Spofforth and other estates in Yorkshire, as well as overseeing his own lands in four counties. Detailed study of the Knaresborough court rolls and Duchy of Lancaster records led to a re-examination of the dating and interpretation of his officeholding and career, particularly in the 1460s and 1470s. He did not regain the stewardship in 1460s, as was believed, but was re-instated in 1471; he was replaced within a few years, probably because of corruption. Principal officeholders at Knaresborough, 1438–1500, are listed, and further unpublished material includes cases which the litigious Plumpton initiated in King's Bench from 1461. His attitudes, often cheating and ruthless, to friends and family, are examined, and his career compared with those of other members of the gentry; Plumpton's status is examined, this being aided by the findings from a rare unpublished fifteenth-century subsidy roll.  相似文献   
25.
Abstract

Pre-Columbian farmers built a variety of earthworks in the Llanos de Mojos, part of the Bolivian Amazon. Raised fields, canals, causeways, and mounds of various types in this region date to ca. 800 B.C.–A.D. 1600. In central Mojos, archaeological work was carried out along the Yacuma, a large west-bank tributary of the Mamoré River. Four ring ditches and two areas of associated raised agricultural fields were mapped. The Global Positioning System was used to document earthworks under the forest canopy which were analyzed within a Geographic Information System. Ceramic evidence is also included. The ring ditches in this study expand the known range of such earthworks in Mojos by 200 km. This revised distribution of ring ditches changes interpretations of the long-term history of Arawak speakers in Mojos and throughout Amazonia. While earthworks in Mojos clearly represent systems of intensive agriculture, they cannot be associated only with Arawak speakers or with Arawak languages.  相似文献   
26.
鸦片战争后签订的一系列不平等条约对军舰驻华特权制度给予了明确的规定。《虎门条约》是外国侵略者"合法"获取军舰驻华特权的开始。美、法等国通过《望厦条约》、《黄埔条约》使这一特权制度日趋完善。在攫取军舰驻泊权的过程中,美国人顾盛使外国军舰驻华特权条款扩展到几乎可以被人任意解释的地步,为日后列强军舰任意游弋中国内水埋下了祸根。通过第一批不平等条约,西方有约国家获得了军舰驻泊特权。第二次鸦片战争中,列强在这一问题上获得了较大突破,此后该制度逐步走向完善。  相似文献   
27.
A set of 104 independently dated archaeomagnetic directions was used to extend the U.S. Southwest reference curve back to 375 cal BC and to calculate isolated mean VGPs centered on 960 cal BC and 2390 cal BC. Prior to this study, most U.S. Southwest reference curves extended to only ca. AD 585. This study employed Sternberg’s moving window technique with variably sized windows, rather than fixed windows, to smooth the dataset into a continuous curve. The size of each averaging window was determined by the density of data captured by the window, such that each window had a minimum data density of 5.0 and a minimum window size of 50 years. This approach differs from previous studies in the U.S. Southwest, which have applied a uniformly sized averaging window to a dataset regardless of the temporal distribution of the data.  相似文献   
28.
Great Smoky Mountains National Park was created in 1934 after decades of popular activism. The National Park Service initially planned to restore wildness to all formerly settled lands through the process of secondary succession, but did not in a valley in the northwest corner of the park, Cades Cove. Transforming the 1200-ha agricultural setting into forest would have eliminated the visual charm highly prized by the tourists who had long come there. Additionally, experts promoted the preservation of Cades Cove's historic–cultural landscape because they falsely perceived the local culture to be a relic of the past. The Park Service acceded, but its commitment to historic preservation was tempered by a concern to minimize its expenses. Consequently, an agricultural permit system was adopted in 1945, which allowed modern farmers to operate on the historic landscape, keeping it open. This cheap method kept open the beautiful vistas of Cades Cove. Unfortunately, the agency's commitment to beauty and economy led to decades of ecological degradation, including water pollution and species extirpation. Only in the last two decades, has park management moved away from its focus on a low-cost, attractive landscape to embrace one that is also ecologically healthy, and thus more sustainable.  相似文献   
29.
王旭 《史学月刊》2003,(7):91-96
无论在重要性还是典型性上,美国中西部在世界区域经济中的地位都是不可小觑的。由美联储发起的研究项目《美国中西部经济:面向未来的历史回顾》,对中西部经济的转型和复兴进行了一番全面的审视和总结。数据翔实,观点颇具权威性,有其独特的研究价值和参考价值。本文概括其内容,并略加评论,以便于我们更准确把握美国老工业区产业结构转型和经济复兴的现状和发展趋势,为我国的老工业区改造提供借鉴。  相似文献   
30.
The vallum is a major earthwork along the south side of Hadrian's Wall. All surface traces of it have been obliterated over a 500-m-long stretch past the fort of Vindobala at Rudchester, Northumberland. To the west of the fort, the vallum's course had previously been delineated by running shear-wave seismic refraction lines to obtain depth profiles of rockhead. We have now run more seismic refraction lines, using both shear waves and compressional waves, to the south-west and south of the fort, and thereby located the complete course of the vallum at Vindobala. The seismic refraction technique is successful at this site because the glacial drift cover is thin, so the vallum ditch was cut down into bedrock. During the second phase of seismic work, compressional waves gave better results than shear waves. Previously, test profiles using compressional waves had failed to locate the vallum ditch west of the fort where the surface elevation is lower; we now interpret that failure as being due to a shallow water table within the drift, which would have eliminated the compressional-wave velocity anomaly. Although the vallum does not pre-date the fort at Vindobala, its asymmetrical course around the fort suggests that it may already have been under construction to the west when the decision to build the fort was taken.  相似文献   
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