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91.
Jennifer M. Miller Elizabeth A. Sawchuk Amy L. R. Reedman Pamela R. Willoughby 《African Archaeological Review》2018,35(3):347-378
Shell beads are well established in the archaeological record of sub-Saharan Africa and appear as early as 75,000 BP; however, most research has focused on ostrich eggshell (OES) and various marine mollusc species. Beads made from various land snails shells (LSS), frequently described as Achatina, also appear to be widespread. Yet tracking their appearance and distribution is difficult because LSS beads are often intentionally or unintentionally lumped with OES beads, there are no directly dated examples, and bead reporting in general is highly variable in the archaeological literature. Nevertheless, Achatina and other potential cases of LSS beads are present at over 80 archaeological sites in at least eight countries, spanning the early Holocene to recent past. Here, we collate published cases and report on several more. We also present a new case from Magubike Rockshelter in southern Tanzania with the first directly dated LSS beads, which we use to illustrate methods for identifying LSS as a raw material. Despite the long history of OES bead production on the continent and the abundance of land snails available throughout the Pleistocene, LSS beads appear only in the late Holocene and are almost exclusively found in Iron Age contexts. We consider possible explanations for the late adoption of land snails as a raw material for beadmaking within the larger context of environmental, economic, and social processes in Holocene Africa. By highlighting the existence of these artifacts, we hope to facilitate more in-depth research on the timing, production, and distribution of LSS beads in African prehistory. 相似文献
92.
Rachel Ama Asaa Engmann 《African Archaeological Review》2018,35(3):379-391
Professor James Kwesi Anquandah was Ghana’s first archaeologist. He was also the first Ghanaian to become head of the Archaeology Department at the University of Ghana, which was the first archaeology department in sub-Saharan Africa, established in 1951. Dedicating his life to Ghanaian archaeology, particularly during the difficult years in Ghana in the 1980s and early 1990s, Anquandah had a significant impact on the development of archaeology in Ghana. In addition to his research, advisory and curatorial work, Professor Anquandah was instrumental in the training of three generations of Ghanaian archaeologists. During the course of a professional career that spanned nearly six decades, Professor Anquandah made archaeology relevant and accessible to all Ghanaians. 相似文献
93.
This study takes a valuation perspective to study how and where products and innovations are gaining ‘economic significance’ in the contemporary economy. Building on a recent research stream in economic geography and urban and regional studies, it highlights that the economic value of many products is not formed within production systems alone, but relies on co-constructed connections between production and consumption systems, playing out across multiple geographies. It distinguishes between three types of economic valuation pathways – namely technical, experiential and identity-based – which although analytically distinct may actually build and reinforce one another. This approach is empirically illustrated with the case of the surf-related economy in the city of San Sebastian (Basque Country, Spain), which is used to make a broader point about the growing relevance of a valuation approach to understand competitive advantage and economic renewal in localized production systems. 相似文献
94.
José León García-Rodríguez Carlos Castilla-Gutiérrez 《European Planning Studies》2018,26(5):1028-1040
The defining element of island regions is their isolation, the separation of the islands from the mainland; there is an inherent notion of natural border. This condition has preserved ecosystems and protected against outside threats, stimulating ‘coevolution’ between man and the environment, a fundamental ingredient of sustainability. But insularity also means the evident added costs of access to markets which, together with territorial limits and the scarcity of basic resources, especially on small islands, hinders their socioeconomic development. These costs are even greater in the case of outlying islands, which suffer from a ‘double insularity’ in the form of both external and internal borders. For this reason, it is common for governments to establish various forms of support, from tax exemptions to the creation of permanent aid funds, like those implemented by the European Union for the outermost regions. This article discusses these aspects in the case of the Canary Islands, an example of a European outermost island region. The findings show that the support measures have not always been favourable for all the islands. 相似文献
95.
Diolinda Ramírez-Gutiérrez Heredina Fernández-Betancort Agustín Santana-Talavera 《International Journal of Heritage Studies》2018,24(6):634-648
In the area of cultural heritage, tourists’ experiences emphasise not only the moment and its personal nature but also socio-cultural traits. These experiences when expressed (social communications) are an important gateway to knowledge about tourists’ sense-making processes. This paper reports on the mediation between tourists and heritage sites via comments on a digital platform (TripAdvisor) about two Spanish tourist destinations with opposing characteristics and four heritage sites, which are analysed. The methodology used seeks to transcend the individual and anecdotal aspects of tourists’ comments. Indeed, the results obtained show the relevance of the humanisation and the discursive weight of heritage contexts in emotional/personal stories. Tendencies observed in non-regulated contexts confirm the role of a complex negotiation at cultural heritage sites and highlight the need to explore possible exchanges of sense in tourists’ encounters with such sites. 相似文献
96.
A simplified model useful for assessing economic losses due to moderate seismicity events in urban areas has been developed by studying the behavior of buildings before yielding their structural system, allowing for nonuniform stiffness along their height. In particular, buildings are modeled as cantilever shear beams with uniform mass and parabolic reduction of lateral stiffness. This particular stiffness distribution is relevant, as it could be expected to occur in buildings where earthquake action is a critical structural design criterion. The equation of motion governing the dynamic behavior of the proposed model is solved analytically, finding mode shapes in terms of first and second zero-order Legendre functions. The solution is verified by comparing it with results obtained from fine mesh finite element models. The effect of reducing the lateral stiffness is then studied in the first five modes of vibration. Results include modal periods, mode shapes, modal participation factors, and derivatives of mode shapes. In general, it is found that effects of reduction of lateral stiffness in mode shapes are moderate when the lateral stiffness in the free end is smaller than about seventy percent of the lateral stiffness at the fixed end, but become significant for larger reductions. Effects are particularly important for the derivative of the mode shapes, which could play a significant role in estimating interstory drift demands in buildings. Model usefulness is showcased by analyzing a test case where both acceleration and drift demands are assessed by considering uniform beams and beams with parabolic stiffness variation, finding notable improvements by considering the latter. 相似文献
97.
98.
San Juan,the Fragile City: Finance Capital,Class, and the Making of Puerto Rico's Economic Crisis 下载免费PDF全文
This paper narrates Puerto Rico's fiscal and financial crisis through a reading of San Juan's urban landscape. We underscore the role of capital in the city, primarily embodied by the local capitalist class (the Criollo bloc) and foreign capitalists. Historically excluded from the manufacturing sector (dominated by US capitalists), the Criollo bloc accumulates its wealth by concentrating financial assets in the city. In times of crisis, the Criollo bloc resorts to the acquisition of new assets and asset exchange with foreign capitalists to remain solvent and provide short‐term solutions to the state's fiscal and financial limits. The survival of the local capitalist class, we demonstrate, is dependent on asset stripping. Drawing on Clyde Woods, we document how asset stripping unevenly redistributes wealth and risks along class and racial lines within a colonial economy. The finance capital/asset stripping basis of San Juan's economy renders it an extremely fragile city, we contend. 相似文献
99.
Cajal SR 《Journal of the history of the neurosciences》2006,15(4):326-340
This paper follows the form of that by Mazzarello that precedes it (Mazzarello, 2006) and presents an imaginary interview with Santiago Ramón y Cajal in December 1906. A few days earlier Cajal had been awarded the Nobel Prize for Physiology or Medicine, an award that he shared equally with Professor Camillo Golgi. Golgi had been recognized for his work as a pioneer into investigations of the nervous system, primarily on account of his discovery of the "black reaction" of silver chromate impregnation of whole nerve cells and their processes. Cajal had been recognized for his implementation of that method and for laying with it the foundations of what was to become modern neuroanatomical science. Paradoxically, the two awardees had been led by their researches to diametrically opposed views of the organization of the nervous system. Golgi believed in a continuous network of axons that formed the basis of all the integrative properties of the nervous system, while Cajal had provided the information that led to the formulation of the neuron doctrine that saw the nervous system as being made up of chains of discontinuous cells joined by polarized functional contacts that we now call synapses. The paper takes the form of an interview with Professor Cajal in the Grand Hotel Stockholm. His responses to questions posed by the imaginary interviewer are all taken from Cajal's own writings. 相似文献
100.
Yaroslav V. Kuzmin 《Journal of Archaeological Research》2008,16(2):163-221
This article focuses on the presence of humans in Siberia and the Russian Far East at the coldest time of the Late Pleistocene,
called the Last Glacial Maximum (LGM) and dated to c. 20,000–18,000 rcbp. Reconstruction of the LGM environment of Siberia,
based on the latest models and compilations, provides a background for human existence in this region. Most of Siberia and
the Russian Far East at c. 20,000–18,000 rcbp was covered by tundra and cool steppe, with some forest formations in the river
valleys. Climate was much colder and drier than it is today. Eighteen Upper Paleolithic sites in Siberia are radiocarbon dated
strictly to the LGM, and at least six of them, located in southern parts of western and eastern Siberia and the Russian Far
East, have solid evidence of occupation during that time span. It seems clear that southern Siberia was populated by humans
even at the height of the LGM, and that there was no dramatic decline or complete disappearance of humans in Siberia at that
time. The degree of human adaptation to periglacial landscapes in the mid-Upper Paleolithic of northern Eurasia was quite
high; humans coped with the cold and dry environmental conditions using microblade technology, artificial shelters, tailored
clothes, and megafaunal bones as fuel.
An erratum to this article can be found at 相似文献