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11.
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   
12.
Migration theories often ignore the role that states play in stimulating migration through public assistance policies. Using the case of Mexico, this article explores the role of the state as a migrant‐producing actor by examining the relationship between migration and social assistance policies in the form of monetary cash transfers. It argues that direct, unconditional cash transfers, like those provided by agricultural programs such as Procampo, rather than providing the incentives needed to retain individuals in their home country, may instead be providing the resources needed to migrate, particularly if the amount of the transfer is insufficient to spur investment. Instead of discouraging migration by enhancing economic opportunities and reducing poverty, such policies can actually make it easier and more appealing for its beneficiaries to migrate.  相似文献   
13.
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   
14.
A noted American authority on China's economy and monetary policy presents a statistical as well as theoretical analysis of a variety of perspectives on the controversy surrounding China's currency, basing his paper on both. The author provides the historical background and comprehensive summaries, focusing on different viewpoints about whether China's currency is undervalued, and thus may contribute to global imbalances. In the paper, he divides observers involved in the controversy into two main camps, namely the ones who find China's trade balances to be sensitive to price effects through exchange rate adjustments and those who emphasize other factors as bearing the responsibility for China's large surpluses, including the U.S. credit bubble emerging before the global financial crisis, as well as a version of Dutch disease.  相似文献   
15.
<正>2007年以前关于抗美援朝战争史(或朝鲜战争史)以及抗美援朝运动研究情况的综述已有几篇①。本文仅对2007年至2010年6月有关抗美援朝的研究成果简略综述。一、研究概况2007年以来出版的有关抗美援朝战争研究的专著约有三十多部,再版书十余部,发表的相关论文上  相似文献   
16.
This article presents and discusses the chronological layout of the final Mousterian and Uluzzian levels of Fumane Cave in northern Italy using 14C, ESR and TL methods. Given its complex sedimentary and cultural succession, Fumane is a key site to assess the Middle–Upper Palaeolithic transition in Southern Europe and to explore Neanderthal behaviour and to compare it with the first Aurignacians. Large ranges defined by the ESR and TL dates cover the radiocarbon ages for units from A11 to A4, respectively, from 42.8 to 32.5 ka BP become progressively younger in agreement with the stratigraphy, despite high dispersions within the same unit. Our estimates using chronometric data seem to support the hypothesis that the sequence may cover almost 10,000 radiocarbon yr and that from comparison with the sedimentological and palaeoecological data, the late Middle Palaeolithic and the early Upper Palaeolithic at Fumane occur in sediments formed under moderately cool to mild climatic conditions correlated to the Hengelo-Interstadial, shifting towards cooler and drier conditions. Finally, comparisons between the Fumane data set and other sites in the North-Adriatic region are discussed.  相似文献   
17.
百人会与美国华人社会   总被引:2,自引:0,他引:2  
建立于 1 990年的“美国华裔百人委员会” ,简称“百人会” ,是美国社会非常有影响的一个华人社团 ,该组织的成员大多是在各自领域取得了杰出成就的精英。在这种背景下 ,该组织在过去的 1 3年里积极充当美国华人的代言人 ,架起中美交往的桥梁 ,为提升美国华人的社会地位、促进中美关系的良性发展做出了重大贡献 ,该组织也深受中美两国政府关注。但遗憾的是 ,至今学术界少有人对它进行全面研究。本文从“百人会”成立的背景及其发挥的作用等方面进行分析 ,以填补美国华侨华人研究的这一小空白。  相似文献   
18.
石斌 《史学月刊》2002,5(12):54-59
研究冷战高潮时期苏东地区的重大政治事件与美国针对苏东内部事态的政策演进历程,有助于更准确地认识“演变”战略的起源与性质。本所利用的档案材料表明,1953年的东德事件对美国决策层初步反省原先过于露骨的旨在激发或助长苏东内部社会紧张乃至“造反”行动的“激变”战略,开始酝酿“演变”战略产生了重要影响。“演变”战略的特征在美国对东德事件的反应中已初露端倪。这一政策转变的原因,除了原有政策在实践中的弊端和斯大林之后苏东形势的变化,也与美国决策的战略指导思想有关。  相似文献   
19.
对朝鲜政策是美国亚太政策中非常重要的一环.伴随着70年代国际局势的相对缓和,美国对朝政策也出现松动.尽管两国间危机不断,但在安全、政治、文化交流等领域美国仍采取了一些主动缓和的措施.然而,作为二战后美国第一场热战的主要对手之一和意识形态上的敌人,美国对改善对朝关系又心存疑虑,同时也受到多方牵制,最终没能有所突破.  相似文献   
20.
ABSTRACT

During its assault on Nanjing, the Japanese Army bombarded and sank the USS Panay, an American gunship, straining the relations between Japan and the United States. During the Nanjing Massacre, to ease tensions with the United States, Japan allowed the staff of the American embassy in Nanjing to make an early return to the city. While investigating allegations that Japanese troops had trespassed on American property and kidnapped and raped a Chinese woman, the American diplomat John M. Allison was struck in the face by a Japanese soldier. The U.S. government exerted pressure on Japan over what was referred to as the “Allison Incident”: under orders from Tokyo, the Japanese occupying force in Nanjing apologized to Allison and placed the officers and soldiers involved in the incident under court-martial. The incident was thereby resolved. However, amidst the furor of the “Allison Incident,” the Chinese woman who had been assaulted was forgotten by both the American and Japanese governments as well as by public opinion. The Japanese soldiers were placed under court-martial not for raping the Chinese woman, but rather for striking an American diplomat. The U.S. government received a great many reports on the atrocities committed by the Japanese Army, but in policy and deed, the American response was limited to safeguarding its national interests in China.  相似文献   
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