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1.
This article investigates how presidential policy attention is allocated across policy tools and whether there is a channeling of tool use by policy area. I also examine whether there is evidence of disproportionate information processing within presidential policy attention allocation and whether it is common across presidential policy tools. Presidential messages, hearings on administrations' legislative proposals, amicus briefs, and executive orders are employed to capture presidential policy tools. The allocation of attention via these four instruments is examined from 1957–2007 in the policy areas of defense and foreign affairs, macroeconomics, banking and commerce, civil rights, law and crime, and labor and immigration. I find that there is a canalization of presidential policy attention by instrument, and that the opportunity structure of policy tools shapes attention allocation. Additionally, I find evidence for punctuated equilibrium theory in the allocation of presidential policy attention via these four tools. When presidents do shift their attention to an issue area, they often attack the issue with some coordination of their policy instruments.  相似文献   
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Abstract

This paper explores the case of the Khami archaeological site, whose degradation by the local communities in recent years was as a result of socio-economic problems caused by the collapse of the Zimbabwean economy combined with the inability of the Zimbabwean government to support the site. We argue that the negative attitude by the local communities towards the management of cultural heritage sites is embedded in the colonial history of the country, and has been driven by the socio-economic difficulties emanating from the collapse of the Zimbabwean economy in recent years. We begin by explaining the history of Khami, its architecture, and the local communities residing around it. We then show and assert that the subsequent degradation of Khami and the landscape around it by the local communities is linked to the socio-economic problems of the country and poverty, which emanated from the collapse of the Zimbabwean economy. In the end, we contend that the economic constraints are part of the reasons why the local communities have from time to time failed to respect the importance of protecting cultural heritage sites in the country.  相似文献   
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稻作农业起源研究中的植物考古学   总被引:1,自引:0,他引:1  
早期稻作农业是植物考古学的一个研究热点。本文首先厘清了农业、栽培和驯化等稻作农业发展中的常用术语。进而对区分野生稻与驯化稻,即反映“半驯化”特征的几个指标包括基盘、谷粒尺寸和植硅石分别展开讨论。文章结合我们对现代野生稻和栽培稻的测量数据以及田螺山的工作,引用了国内外诸多考古实例和最新的分子学证据,证据表明上述几个指标在某些程度上多少可以作为性状来判断驯化稻是否已经出现,但是随着农业景观概念的提出,耕地杂草群落作为农田系统研究的证据.为稻作农业出现和发展研究展开了新视野。  相似文献   
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档案信息资源开发利用之管见   总被引:1,自引:0,他引:1  
王萍 《攀登》2009,28(5):126-128
推进档案信息资源的开发利用,对经济发展和社会建设具有重要的促进作用。只有从加强档案基础工作和协调管理入手,发挥档案人员的聪明才智,充分借助和运用现代高科技手段,才能使档案信息资源在新的历史时期发挥其应有作用。  相似文献   
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An archaeological GIS is used to examine the late eighteenth-century cultural landscape of St. John, US Virgin Islands. Land use patterns are reconstructed using a combination of historic maps, tax records, and survey reconnaissance. The study demonstrates significant, heretofore undocumented, transitions taking place that reflect dynamic cultural and economic change within Danish West Indian plantation society that includes a significant trend towards land ownership by free-colored St. Johnians more than a half a century before emancipation. These venues of freedom are discussed in relation to broader patterns of estate consolidation and economic shifts.  相似文献   
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龙燕宁 《攀登》2009,28(4):122-124
做好经济新闻报道对于贯彻党和国家有关经济方面的方针、政策,对于客观理性地分析世界经济局势、评判我国经济现状和走向、保持经济平稳较快发展、满足人民群众日益增长的信息需求都具有十分重要的意义。文章指出了长期以来我们在经济新闻报道方面存在的问题,并就这些问题提出了改进方法。  相似文献   
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The fluorite deposits of Asturias (northern Iberian Peninsula) are hosted by rocks of Permo‐Triassic and Palaeozoic age. Fluid inclusions in ore and gangue minerals show homogenization temperatures from 80 to 170°C and the presence of two types of fluids: an H2O–NaCl low‐salinity fluid (<8 eq. wt% NaCl) and an H2O–NaCl–CaCl2 fluid (7–13 wt% NaCl and 11–14 wt% CaCl2). The low salinity and the Cl/Br and Na/Br ratios (Cl/Brmolar 100–700 and Na/Brmolar 20–700) are consistent with an evaporated sea water origin of this fluid. The other end‐member of the mixture was highly saline brine with high Cl/Br and Na/Br ratios (Cl/Brmolar 700–13 000 and Na/Brmolar 700–11 000) generated after dissolution of Triassic age evaporites. LA‐ICP‐MS analyses of fluid inclusions in fluorite reveal higher Zn, Pb and Ba contents in the high‐salinity fluids (160–500, 90–170, 320–480 p.p.m. respectively) than in the low‐salinity fluid (75–230, 25–150 and 100–300 p.p.m. respectively). The metal content of the fluids appears to decrease from E to W, from Berbes to La Collada and to Villabona. The source of F is probably related to leaching of volcanic rocks of Permian age. Brines circulated along faults into the Palaeozoic basement. Evaporated sea water was present in permeable rocks and faults along or above the unconformity between the Permo‐Triassic sediments and the Palaeozoic basement. Mineralization formed when the deep brines mixed with the surficial fluids in carbonates, breccias and fractures resulting in the formation of veins and stratabound bodies of fluorite, barite, calcite, dolomite and quartz and minor amounts of sulphides. Fluid movement and mineralization occurred between Late Triassic and Late Jurassic times, probably associated with rifting events related to the opening of the Atlantic Ocean. This model is also consistent with the geodynamic setting of other fluorite‐rich districts in Europe.  相似文献   
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