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21.
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   
22.
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   
23.
Wainman, C.C., Hannaford, C., Mantle, D. & McCabe, P.J., April.2018. Utilizing U–Pb CA-TIMS dating to calibrate the Middle to Late Jurassic spore-pollen zonation of the Surat Basin, Australia to the geological time-scale. Alcheringa XX, xx-xx.

Spore-pollen palynostratigraphy is commonly used to subdivide and correlate Jurassic continental successions in eastern Australia and thus aid the construction of geological models for the petroleum and coal industries. However, the current spore-pollen framework has only been tenuously calibrated to the geological time-scale. Age determinations are reliant on indirect correlations of ammonite and dinoflagellate assemblages from New Zealand, the North West Shelf of Australia and Southeast Asia to the standard European stages. New uranium-lead chemical abrasion thermal ionization mass spectrometry (U–Pb CA-TIMS) dates from 19 tuff beds in the Middle–Upper Jurassic Injune Creek Group of the Surat Basin enables regional spore-pollen palynostratigraphic zones to be precisely dated for the first time. These results show the base of the APJ4.2 and APJ4.3 subzones are similar in age to previous estimates (Middle Jurassic, Bathonian) from indirect palynostratigraphic correlation. However, the base of the APJ5 Zone and the APJ6.1 Subzone may be somewhat younger than previously estimated, possibly by as much as 2.5 and 4.2 Myrs, respectively. The continued utilization of U–Pb CA-TIMS dates will further refine the absolute ages of these zones, improve the inter- and intra-basinal correlation of Middle–Upper Jurassic strata in eastern Australian basins and greatly enhance intercontinental correlations.

Carmine Christopher Wainman [] and Peter James McCabe [] Australian School of Petroleum, University of Adelaide, SA, 5005, Australia; Carey Hannaford [] and Daniel Mantle [] MGPalaeo Pty Ltd, 5 Arvida Street, Malaga, WA, 6090, WA, Australia.  相似文献   
24.
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   
25.
Brexit means that regions of the United Kingdom will lose access to the EU Cohesion Policy. Have EU funds been effective, and what might be the consequences of an interruption of EU financial support? This paper studies the impact of “Objective 1” funding—the highest form of EU aid—in Cornwall and South Yorkshire, two of the U.K.’s most subsidized regions. Counterfactual methodologies assessing their labor market and economic performance provide evidence of a positive effect of EU Objective 1 funds. When in 2006 South Yorkshire lost Objective 1 eligibility, this massively reduced its share of EU funds and the region was unable to sustain the gains obtained in previous years. This suggests that while Structural Funds may be effectively improving socio‐economic conditions of poorer regions, the performance of subsidized areas could be deeply affected by a reduction (or worse, an interruption) of EU aid.  相似文献   
26.
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   
27.
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   
28.
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   
29.
郭永虎  李晔 《史学集刊》2005,9(4):75-81
1949至1969年间美国中央情报局向西藏分裂势力提供了一系列准军事援助。该援助行动的实质是为美国远东战略利益服务,其目标是利用西藏分裂势力遏制与分裂中国,具体内容主要包括:为西藏叛乱分子提供情报和准军事训练技术;在西藏实施公路袭扰和破坏行动;为达赖集团提供军事物资和活动经费;与印度情报机构开展针对中国的情报合作等等。  相似文献   
30.
Casas Grandes, or Paquimé, is located in northwestern Chihuahua, Mexico, although it is one of the pueblo-style cultures that are best known from the adjacent southwestern U.S. At its apogee (ca. A.D. 1200–1450), Casas Grandes has been characterized as the largest and most complex prehistoric community in the puebloan world. It is further famous both as the center of one of the major interaction systems of the region, as well as a link between the cultures of Mesoamerica and those of the U.S. Southwest. Despite its acknowledged status as one of late prehistoric North America's few indigenous complex societies, the Casas Grandes polity has been so little studied that most aspects of its size, structure, level of centralization, and mode of operation remain obscure. The writers' work in Chihuahua has been designed to remedy this situation. In contrast to the original and highly influential interpretation that has prevailed for the last 25 years, the work reported here argues that the Casas Grandes polity, like its Chacoan and Hohokam counterparts of the adjacent southwestern U.S., existed at an intermediate level of sociopolitical complexity, so that it was not able to exert a uniform hegemony even over its near neighbors. Envisioned instead is a less comprehensive, less centralized situation of irregular control in a politically unstable context.  相似文献   
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