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Cristian Kaufmann María A. Gutiérrez María C. Álvarez Mariela E. González Agustina Massigoge 《Journal of archaeological science》2011,38(2):334-344
Hydrodynamic sorting is a taphonomic process able to transport and scatter bones deposited in archaeological and paleontological sites. This study presents the results of experimentation performed in an artificial flume with guanaco (Lama guanicoe) bones of different ontogenetic development, dry and saturated in water, in hydric flows velocities of 15 and 30 cm/s. The obtained results show that bone global density, the age of the individual, the dry or wet bone state, and the hydric flow velocity influence significantly bone dispersion. In this way, bones from immature individuals with unfused secondary growth centers and relatively low bulk density have better possibility of being transported than fused bones from adult individuals. Taking into account the results obtained in this experimentation and the feasibility of discriminating age categories in fossil assemblages, two bone groups with differential potential transport are presented in this paper. These transport groups constitute a methodological tool to evaluate the role hydric current may had played in the formation of a fossil assemblage. 相似文献
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Juan Gabriel Tirado Ballesteros María Hernández Hernández 《European Planning Studies》2019,27(2):396-414
ABSTRACTFor many European rural areas, the rural development programmes based on the LEADER approach constitute the main policy for promoting tourism. Going a step further than a rural development programme, LEADER represents an ideal method for overcoming some of the challenges involved in rural tourism development, such as the integration of tourism supply through public-private organizations or the coordination of multi-level policies. Despite its potential, there are difficulties involved in putting this approach into practice. This article aims to provide in-depth understanding of the challenges faced by some managers responsible for developing tourism strategies through the LEADER approach. To do this, semi-structured in-depth interviews have been held with Local Action Groups managers from Castilla-La Mancha (Spain). The main findings reveal that the actions of regional governments lead to the limitation and strangulation of the principle of subsidiarity according with the LAG manager? opinion. 相似文献