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11.
Policies governing the sale of raw milk—making the sales of raw milk more permissive—are gaining traction on the legislative agendas of dozens of states. This paper examines one contributor to this movement on the policy agenda: the role of competitive framing. By combining theoretical approaches from policy studies and political psychology theories of competitive framing, we offer evidence supporting the recent relative success of raw milk activists in several state legislatures. Using an Internet survey‐based experiment with a sample size of 1,630 respondents from seven Midwestern states, we show that a frame emphasizing consumer choice and food freedom is more effective than the frame that dominates among the policy establishment, that emphasizing public health risks. This is true in both one‐sided and competitive framing contexts. We further show that those previously aware of this issue were less influenced by the public health frame than those naïve to the issue. Our results suggest that the pro‐raw milk movement may be making strides on the state policy agenda because their frames are more resonant among the public. We also highlight the advantages gained from considering psychological and policy processes simultaneously to understand policy change.  相似文献   
12.
The Lv family tombs in Lantian, Shaanxi Province are one of the most important archaeological sites of China in recent years, providing numerous objects and a wealth of information for the study of the history of the Northern Song dynasty. There were a large number of exquisite cultural relics unearthed from the tombs, including one porcelain box containing white powder, which was identified as women's makeup. The phase composition, microstructure, thermal properties and characteristics of the trace elements in the unearthed white cosmetic powder were comprehensively analysed by X‐ray diffraction (XRD), scanning electron microscopy (SEM), differential scanning calorimetry – thermogravimetry (DSC–TG), Fourier transform infrared (FT–IR) microscopy and inductively coupled plasma atomic emission spectroscopy (ICP–AES). The white makeup powder was determined to be a product made from high‐quality freshwater pearls. These results, for the first time, showed evidence that freshwater pearl powder was used as a cosmetic in ancient China using archaeological objects, providing scientific evidence and new clues to enrich and expand research into the ancient Chinese cosmetic materials.  相似文献   
13.
The Tekta? Burnu ship (440–425 BC) sank along a rough and desolate stretch of the Turkish Aegean coast. Archaeological excavation of the shipwreck site by the Institute of Nautical Archaeology at Texas A&M University resulted in the retrieval of hundreds of small fragments from the ship's wooden hull and its metal fasteners. Recent study of this artefact assemblage suggests that the coastal trader was built with pine planks and made‐frames, and assembled by a shell‐based construction method. Fasteners include pegged mortise‐and‐tenon joints and double‐clenched copper nails, and the ship may have had laced extremities consistent with other contemporaneous shipwrecks.  相似文献   
14.
This paper continues the characterization of the lead isotopic fingerprint of ancient copper mines in the north‐west of Spain. In this work, the lead isotopic compositions found in copper ores from the La Profunda mine are presented. Azurites and malachites sampled from this deposit were subjected to lead isotope analysis by multicollector ICP–MS. The results showed a clear radiogenic lead signature compatible with the presence of uranium‐rich minerals (such as zeunerite) in the same mining complex. Moreover, a rare copper artefact, found in the galleries of the mine during its modern exploitation, was also analysed and showed that local mineral was used for its manufacturing.  相似文献   
15.
在一二八、八一三事变中,上海两次惨遭日军炮火蹂躏,尤其是闸北的繁华地带东北、西南两处,先后因日军轰炸使三十年的建设成就荡然无存。日本的侵华战争不但中断了闸北的现代化建设,还直接导致了该地区的长期沉沦。  相似文献   
16.
20世纪50年代中国在引进基础上的技术创新   总被引:2,自引:0,他引:2  
20世纪50年代中国的技术引进和技术创新活动集中在“一五”时期和“大跃进”时期,虽然这两个时期在引进基础上的创新活动都是在重工业优先发展战略下的体制框架内进行的,但在引进技术的行业构成、规模、项目建设的实施和技术的消化乃至技术创新机制、成效等方面都有所不同。“一五”时期采用了全面、系统、灵活多样的方式和重点攻关,在消化、吸收引进技术方面取得了明显的成效,某些领域实现了技术再造,技术创新能力得到了迅速积累,但从总体上看仍处于对引进技术的翻版、修改阶段。“大跃进”时期的技术创新机制被严重干扰,群众运动代替了深入细致的科学研究,在群众性技术革新运动中引进基础上的创新活动格外活跃,通过技术革新运动学会了自行制造一些成套设备、生产工艺,但并没有从产业部门或行业整体上真正实现引进基础上的再次创新,其整体水平依然停留在对引进技术的“初级模仿”阶段。  相似文献   
17.
从卜辞看洹北商城一号宫殿的性质   总被引:1,自引:0,他引:1  
将卜辞中有关宗庙的祭祀活动和祭祀场所资料与洹北商城一号宫殿基址的祭祀遗存相对照,内涵基本相合,从而证明洹北商城一号宫殿为商王的宗庙.  相似文献   
18.
本文考证了渭南、华县之间的赤水河“桥上桥”的建造年代及形成原因。通过对有关历史资料深入研究,确证下桥始建于清初(1667年),上桥则建于清朝中叶(1832年)。赤水河中上游的过度垦殖和植被破坏带来的生态环境恶化造成了下游河床泥沙淤积,形成了地面悬河,原赤水桥为泥沙淹塞,失去功能,故不得不在桥上建桥。桥上桥的形成是当地生态环境变化的结果和标志。  相似文献   
19.
从考古看丝绸之路祁山道的形成   总被引:1,自引:0,他引:1  
四川是中国古代丝绸之路的起点之一。北经陇南通向陇右天水地区的祁山古道,是四川与黄河流域沟通并通向中亚、西亚、北非和欧洲的重要的通道之一,但长期以来被学术界忽视。从新石器时代早期至晚期,逐渐形成了一条以渭河上游的天水为中心.东连渭河中下游的关中平原乃至中原,南经陇南至川北嘉陵江上游,然后经涪江、成都平原、大渡河下游至云贵高原西北的彩陶文化传播线路。夏商西周时期,中原夏文化、西北寺洼和早秦文化经天水、陇南与早蜀文明发生了密切联系。春秋战国时期,在区域交通的基础上,文化传播线路形成了川蜀经陇南、天水与中亚、西亚、北亚地区联通的国际贸易通道。  相似文献   
20.
张素霞 《史学月刊》2003,(9):117-120
从1998—2002年《史学月刊》的发文作者发文量、合作度、地区和机构分布、年龄、职称及他们利用文献状况的统计分析,可以看出《史学月刊》不愧为综合性的史学专业核心期刊,它拥有一支高素质、高水平、高学历、高职称的作者队伍。  相似文献   
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