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Four decades have passed since Harlan and Stemler (1976) proposed the eastern Sahelian zone as the most likely center of Sorghum bicolor domestication. Recently, new data on seed impressions on Butana Group pottery, from the fourth millennium BC in the southern Atbai region of the far eastern Sahelian Belt in Africa, show evidence for cultivation activities of sorghum displaying some domestication traits. Pennisetum glaucum may have been undergoing domestication shortly thereafter in the western Sahel, as finds of fully domesticated pearl millet are present in southeastern Mali by the second half of the third millennium BC, and present in eastern Sudan by the early second millennium BC. The dispersal of the latter to India took less than 1000 years according to present data. Here, we review the middle Holocene Sudanese archaeological data for the first time, to situate the origins and spread of these two native summer rainfall cereals in what is proposed to be their eastern Sahelian Sudan gateway to the Red Sea and the Indian Ocean trade.  相似文献   
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Since the devolution of welfare policymaking to the states after the passage of the 1996 Personal Responsibility and Work Opportunity Reconciliation Act, there has been contentious debate about drug testing welfare applicants. Beyond elite rhetoric and debate points about the implications of welfare drug testing, extant research remains limited insofar as providing theoretical understanding about what factors influence state proposal of legislation requiring welfare applicants to submit to drug tests. I develop and test expectations that derive from research on welfare attitudes, social construction theory, and policy design—specifically, hypotheses that the proportion of blacks on state temporary assistance for needy families caseloads, as well as state‐aggregate levels of symbolic racism, significantly influence state proposal of drug testing legislation. My multilevel analysis of every state proposal of welfare drug testing legislation from 2008 to 2014 yields strong evidence in support of these hypotheses and paints a more complete picture of the influence of racial attitudes on state welfare policymaking. Specifically, while much research finds evidence of institutional racial biases in the implementation of welfare policy, the evidence presented herein shows that these biases, as well as public biases, influence policymaking at the proposal stage. Implications of these findings are discussed in light of recent significant electoral gains made by Republicans in state legislatures.  相似文献   
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The Irish dimension of Anglo-American relations is a relatively marginalized aspect of the historiography of transatlantic studies. Historians have focused on the role of the Clinton administration in the Northern Ireland “peace process” but previous American contributions also warrant attention. As the Speaker of the United States House of Representatives, Thomas P. “Tip” O’Neill was one of the most prominent Irish-American politicians. This article demonstrates O’Neill's attempts to ensure that the American contribution to the Anglo-Irish process steadily increased, despite the transition from arguably his natural political ally in the President Jimmy Carter administration to President Ronald Reagan in 1981. O’Neill's interest in Northern Ireland and position as speaker helped ensure that Carter's promise of financial aid to Northern Ireland in 1977 following progress in the political process was fulfilled in March 1986.  相似文献   
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This paper explores the effectiveness of a tutorial-based approach in supporting the development of geography undergraduates’ ethical thinking. It was found that overall the intervention had a statistically significant impact on students’ ethical thinking scores as assessed using a Meta-Ethical Questionnaire. The initiative led to a convergence of scores, having a bigger impact on those who had a relatively low score prior to the intervention. Interestingly, the approach had the biggest impact on students who self-identified as physical geographers. Unlike some previous research, there was little evidence of difference between male and female students.  相似文献   
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