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801.
Martin Gimm 《东方研究杂志》2017,65(1):233-236
802.
Martin Franz Sebastian Rolfsmeier 《Geografiska annaler. Series B, Human geography》2016,98(3):271-286
The expansion of primary breeding companies for layer hens has reached a global scale. Two groups of companies, the Dutch Hendrix Genetics BV and the German EW Group GmbH, dominate the trade with layer hens for industrial egg production in most countries of the world. This article aims to identify the main actors of industrial egg production and to analyse the structure of the global layer hen production network. Furthermore, this paper examines the importance of brands and quality within the production network. While the primary breeding level is discussed on a global scale, the secondary breeding level and the egg production is analysed at a national level for Germany. Since the importance of brands is strongly related to the quality of the products and the trust therein, the structure of the layer hen production network in regard to the role of brands and trust is evaluated. For this evaluation, the authors combined the global production network approach with elements of the convention theory. 相似文献
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Martin Finné Karin Holmgren Hanna S. Sundqvist Erika Weiberg Michael Lindblom 《Journal of archaeological science》2011,38(12):3153-3173
The eastern Mediterranean, with its long archaeological and historical records, provides a unique opportunity to study human responses to climate variability. We review paleoclimate data and reconstructions from the region with a focus on the last 6000 years. We aim to provide an up-to-date source of information on climate variability and to outline present limitations and future opportunities. The review work is threefold: (1) literature review, (2) spatial and temporal analysis of proxy records, and (3) statistical estimation of uncertainties in present paleoclimate reconstructions (temperature, °C). On a regional scale the review reveals a wetter situation from 6000 to 5400 yrs BP (note: all ages in this paper are in calibrated years before present (i.e. before 1950), abbreviated yrs BP, unless otherwise stated). This is followed by a less wet period leading up to one of fully-developed aridity from c. 4600 yrs BP. There is a need for more high-resolution paleoclimate records, in order to (i) better understand regional patterns and trends versus local climate variability and to (ii) fill the gap of data from some regions, such as the Near East, Greece and Egypt. Further, we evaluate the regional occurrence of a proposed widespread climate event at 4200 yrs BP. This proposed climate anomaly has been used to explain profound changes in human societies at different locations in the region around this time. We suggest that although aridity was widespread around 4200 yrs BP in the eastern Mediterranean region, there is not enough evidence to support the notion of a climate event with rapidly drying conditions in this region. 相似文献
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Martin Ježek 《Journal of Anthropological Archaeology》2013,32(4):713-731
European archaeological collections record hundreds of thousands of stone artefacts from the Early Middle Ages described as whetstones. However, traces of non-ferrous metals, including precious metals preserved on a number of such artefacts. Many of the finds served in fact as touchstones – tools to test the quality of a particular metal. These artefacts are concentrated mainly in Vendel and Viking Age and Slavic coastal settlements and trade centres in the Baltic Sea basin, the coast and islands of Northwestern Europe, at Central and Eastern European fortresses and suburbia. Many finds also come from rural settings. In early medieval graves the touchstones join balance scales and weights as a sign of the buried individual’s access to precious metals. Especially the rural finds with traces of precious metal provide a strong reason for a revision of present views on the social stratification of the early medieval society in Europe. Chemical microanalysis allows identifying the composition of the alloys. Besides new perspectives on the fields of the social history and the circulation of precious metals, the method also provides new information for the field of archaeometallurgy. 相似文献
808.
Martin Hall 《Journal of archaeological science》1984,11(3):223-235
The Mfolozi and Hluhluwe Valleys of southeastern Africa are representative of a sub-tropical biome and have archaeological evidence for farming settlement spanning more than 1500 years. By collecting information on soils and plant communities within the same sample frame as archaeological data, the relative importance of environmental and anthropomorphic influences can be assessed. It is argued that, although climate and soils have determined the overall distribution of plant communities, human land use has had a considerable effect on the composition of both woodland and grassland. The nature of this interaction between man and environment provides inferential data on prehistoric economies and also aids the formulation of conservation policies in protected areas. 相似文献
809.
Ged Martin 《The American review of Canadian studies》2013,43(3):215-234
810.