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991.
The ‘pollen washes’ technique, based on the analysis of the pollen embedded in the porous surface of archaeological artefacts, is developed for investigating past plant usage and consumption and to characterize the functionality of artefacts related to plant processing, gathering and storage. The research presented results in relevant methodological improvements of this technique, which has never previously been applied on materials from European contexts. The improvements allow: (1) faster analysis of a broad series of artefacts or those with large use‐surface areas likely to retain more pollen; and (2) a more thorough, deeper and precise cleaning method, allowing the study of smoother artefacts. Finally, the recovery of Trifolium‐group pollen from a macro‐lithic tool from Xicotó rock shelter (Montsec ranges, Spain) demonstrates that the pollen washes technique can reveal new insights into both the use and consumption of wild and domestic plants by prehistoric societies, and the functionality of archaeological objects whose interpretation is still problematic.  相似文献   
992.
993.
The concept of nostalgia has an invaluable advantage: In contrast to other cultural concepts, it has an exact date of birth. It was in 1688 when the medic Johannes Hofer published a thesis in which he described an illness he termed with the neologism “nostalgia.” But instead of following the academic and larger cultural discourses that evolved from this starting point until the present, the question that deserves some attention is which temporal setting goes along with the concept of nostalgia. Most of the experts on nostalgia as a sickness during the last three and a half centuries did not diagnose themselves but others, quite often patients from rural areas who had to leave home to work abroad, where they became nostalgic. With this diagnosis these experts also established a certain time‐model, because they separated a “modern” time‐model of irreversibility from a “nostalgic” time‐model of reversibility. If we take a closer look at the nostalgia diagnosis and its consequences, we might also gain some ideas for our thinking about the theory of history.  相似文献   
994.
This paper examines the extent to which sectoral diversification can act as an insurance mechanism against fluctuations in regional gross value‐added growth rates. Portfolio theory is applied to the growth‐instability properties of German districts. Furthermore, a comprehensive diversification measure is defined. Stochastic Frontier Analysis is deployed in order to estimate whether diversification allows regions to achieve more efficient growth‐instability combinations. The results confirm that diversification does generate such effects. Spatial interactions do also play a role: The effects are less pronounced for regions whose economic performance is mainly driven by the surrounding regions.  相似文献   
995.
Informal housing,spatial structure,and city compactness   总被引:1,自引:0,他引:1       下载免费PDF全文
This paper develops a monocentric city model with a formal and an informal sector in the housing industry. While formal developers build houses renting land from landowners, informal developers use land for free. However, informal developers must incur defensive expenditures to avoid government intervention. In equilibrium, at any distance of the central business district (CBD), informal developers use land until the value of the marginal productivity of land equals the defensive expenditures per unit of land. The model shows the land allocated to produce short informal (tall formal) buildings increases (decreases) with distance to the CBD. Thus, the model introduces a new source of spatial variation of building height. The model also shows that a higher level of informal housing increases the spatial size of a city and reduces the height of its buildings.  相似文献   
996.
Yunpeng Zhang 《对极》2018,50(4):1120-1140
This article examines the securitisation of land development rights under the dipiao scheme in Chongqing, China. It argues that this instrument is based on the dispossession and exploitation of rural households but these unequal relations have been concealed and naturalised through the complex geographies and temporalities of dispossessory arrangements, financing mechanisms and discursive tactics. By overcoming political barriers to land commodification and dispossession in this way, the Chongqing government has expanded the frontier of commodifiable land and sustained a land‐based, urban‐centric and debt‐financed accumulation. Instead of narrowing the urban–rural divide, this instrument reproduces and solidifies it. On this basis, the article argues that conceptual and political innovations for inclusive and equitable development needs to shift the attention from land to people.  相似文献   
997.
Historical maps have the potential to aid archaeological investigations into the persistence of Native American settlements during the mid-19th century, a time when many Native communities disappear from archaeological view. Focusing on Tomales Bay in central California, we evaluate the usefulness of historical maps as a way to discover and interpret archaeological deposits dating to the period, with the aim of better understanding indigenous patterns of residence at the transition from missionary to settler colonialism. In particular, we focus on diseños and plats created to document Mexican-era land grants as well as early maps produced by the General Land Office and United States Coast Survey. Although we note inconsistencies regarding the inclusion of indigenous settlements on historical maps, our case study offers an example of how archaeologists can employ historical maps and targeted archaeological ground-truthing to discover sites that are poorly represented in the historical and archaeological records.  相似文献   
998.
秦汉时期岭南地区的墓葬中大量出土各种类型的联体陶器,被普遍认为是当地考古学文化的特色。这些联体陶器的分布、形制、共出陶器和墓葬背景呈现如下特点:它们在岭南地区呈现以秦汉郡治为中心的多点辐射式分布,数量和类型呈现"故王都—郡治—一般县城"的层级落差,近海较内地数量多、类型丰富;在发展脉络上,从多种类型到比较单一的五联罐再到急骤消失;联体陶器应该是一种南越国时期在外地工艺冲击下出现的本土化产品,与"边地半月形地带"和环地中海地区的kernos/pseudokernos可能存在渊源关系。  相似文献   
999.
随着老龄化的快速发展,老年人在中国已经构成重要的群体,而因肥胖导致的一系列慢性疾病严重影响老年人的寿命和生命质量。身体质量指数(BMI)是衡量肥胖的重要指标。本文以女性老年人为研究对象,运用有序多分类Logistic回归模型,分析建成环境对女性老年人身体质量指数的影响。结果表明,居住地附近是否有适宜的休闲体力活动场所、居住地到休闲体力活动场所的步行时间、一周内去商场的频率、高热量食物的可获得性等建成环境变量与因变量女性老年人BMI等级存在显著联系。根据研究结论,从城市规划的角度提出建成环境优化建议,为构建老龄友好型的健康城市提供基础。  相似文献   
1000.
Two iron‐age shipwrecks, associated with Phoenician ceramics, were discovered at the Playa de la Isla in Mazarrón, Spain. This preliminary report describes hitherto unknown boatbuilding features of the Mazarrón 1 hull remains. The vessel presents hybrid boatbuilding techniques using both pegged mortise‐and‐tenon plank‐edge fasteners and sewn seams employing longitudinal continuous stitching, and a unique keel scarf. It is an important source of information for the development of shipbuilding in the western Mediterranean during the Iron Age.  相似文献   
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