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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   
2.
Is a third passage to the past possible, beyond Elton's and Fogel's two roads of narrative history and scientific/quantitative history? One that would combine narrative history's focus on the event, on individuals and their actions, at a particular time and place, to scientific/quantitative history's emphasis on explicit behavioral models based on social-science theories? That is the question this article addresses. It illustrates a computer-assisted methodology for the study of narrative—quantitative narrative analysis (QNA)—that does just that. Based on the 5 Ws + H of narrative—Who, What, When, Where, Why, and How—QNA quantifies events without losing the event itself, without losing people behind numbers, diachronic time behind synchronic statistical coefficients. When used in conjunction with dynamic and interactive data visualization tools (and new natural language processing tools), QNA may provide a third unforeseen road to the past.  相似文献   
3.
    
The commercial pelt trade between Native Americans and Europeans flourished in the 17th and 18th centuries. However, the impact of this economic change and increased hide processing efforts on Native American upper limb morphology is unknown. The hide scraping hypothesis, tested in living subjects, suggests that hide processing efforts may lead to significant changes in humeral morphology. Two modern human Native North American skeletal collections from south‐western Virginia, USA, were studied to test if intensive hide processing led to changes in humeral morphology. At the earlier Late Woodland Crab Orchard site, animal skins and furs were prepared for household use. During the occupation of the later early historic Trigg site, processing activities intensified to produce surplus hides for the commercial pelt trade. In this study, the cross‐sectional geometric properties at the mid‐distal humerus (35% of length) of Crab Orchard and Trigg adult males and females were examined. We assessed whether Trigg site individuals had increased humeral symmetry, changes to diaphyseal shape, and increased robusticity. Additionally, humerus morphological properties were compared between males and females to assess if there were sex‐based differences. Trigg site males had greater humeral robusticity than Crab Orchard males. The humeri of females from the Trigg and Crab Orchard sites were both relatively anteroposterior strengthened and displayed quite low levels of bilateral asymmetry. This pattern suggests that females at both sites may have employed techniques that involved bimanual hide processing tools. The differences between the morphologies predicted and those observed in these Native American populations may indicate (a) adaptation to bimanual hide processing techniques or (b) adaptation to osteogenic tasks not involved in hide processing but associated with postcontact economic changes.  相似文献   
4.
The results obtained from the multi-analytic compositional characterization of ceramic pastes and paints of the Santa María style, from the El Bolsón valley (Belén Department, Catamarca Province, Argentina), are presented here. This pottery style had a wide regional distribution in Northwestern Argentina between ca. 1000 and1600 ce and is characterized by its complex iconography painted in black, cream and red. The analyses show that the containers correspond to the technical tradition of using grog temper and suggest that its manufacture involved a double firing process. This reveals a new practice for the time.  相似文献   
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Bitumen, found in abundance in Mesoamerica’s southern Gulf Coast region in natural seeps and in many archeological contexts, is an important economic resource and exchange item that has received little consideration in Mesoamerica. Analyses of archeological, ethnoarcheological, and experimental data provide insights on the organization of bitumen processing activities, and the end product (archeological bitumen), which the Olmec (1200–400 BC) used in the production of many items. Archeological data are derived from investigations at El Remolino and Paso los Ortices— two Early Formative period levee sites in the San Lorenzo Olmec region. Our findings suggest that among the Olmec, bitumen processing was organized as a specialized activity, involving multiple production stages, but not necessarily elite involvement or control.  相似文献   
7.
This paper describes the methods and results of ethnographically-based replicative seed processing experiments conducted on Australian Macrozamia moorei seeds. Archaeological evidence indicates that these seeds were consumed by Australian hunter–gatherers in both the Pleistocene and Holocene. The experiments identified three features indicative of human processing and tested the effect of different processing variables (striking position, indentor type, thermal modification and presence of outer flesh) on the frequency of these diagnostic criteria. The results demonstrate that it is possible to use the physical modifications on individual seed specimens to identify the anthropogenic fracture of seeds and specific methods used to process them. These criteria were used in the analysis of M. moorei seeds from mid-Holocene-aged archaeological sites in central Queensland, Australia. The results indicate that seeds with and without sarcotesta were processed using a wooden indentor via side striking techniques.  相似文献   
8.
There is a long history of human interaction with plants of the Aroideae subfamily (Araceae). Despite these plants' chemical defenses against animal and vegetal predation, humans have targeted their starchy corms, tubers and rhizomes for dietary purposes. In the Eastern Woodlands of North America, early Europeans described the Native population as utilizing the highly acridic Peltandra virginica (arrow arum) for subsistence needs. In order to render this resource edible, however, the acridic principle first needs to be eliminated. Our study investigates the affect these processing activities have on the integrity of arrow arum starch grains. Findings from this study demonstrate that environmental variables specific to individual processing procedures may be more influential on starch grain survival than simply the temperatures reached during cooking.  相似文献   
9.
龙门石窟奉先寺的安全长期受到风化及渗水等病害影响。针对奉先寺石造像阿难头部区域及卢舍那大佛南侧渗水区域,利用红外成像设备对该区域进行为期一年的实时监测,并借助MATLAB语言的图像处理技术对大量红外图像进行数据分析。结果发现佛像头部裂隙处存在温差引起的循环热应力,该温差主要由灌浆加固区域和岩体本体之间热传导性能差异导致,且晴天上午前后的温差应力变化最显著;归纳了监测期间降雨和渗水发生的时间规律,统计得出了不同区域渗水程度的差异。将红外成像和大数据分析结合应用于石窟预防性保护中,实现了对病害同时进行图像监测和统计评估,为其他石窟寺的监测与数据分析工作提供参考。  相似文献   
10.
随着经济全球化的深入发展,自由经济区在推动国民经济总体发展战略实施与经济体制改革、促进区域经济和城市化发展等方面发挥了重要作用。20世纪60年代,台湾建立了世界上第一个正式以\"出口加工区\"命名的经济型特区,通过不断转型升级推动了台湾的工业化和社会经济发展。本文通过文献归纳,总结了台湾经历的\"出口加工区-科学工业园区-自由贸易港-自由经济示范区\"四个发展阶段的特点;从目标、政策法规、管理、产业和空间结构入手,归纳出台湾自由经济区的形成演化规律;并认为要素、产业、效益、创新、政策、市场、环境各动力因素相互作用,构成推动其演化的动力机制。本研究对完善自由经济区形成演化理论探索和国内自贸区建设具有一定参考意义。  相似文献   
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