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71.
Over the past five decades, archaeologists have proposed a wide range of methods for the study of spatial organization within hunter-gatherer sites. Many of these methods sought to identify the spatial location of activities based on patterns of behavior observed in ethnographic contexts. While this resulted in productive observations at certain sites, many of these methods were tailored to specific situations and thus could not be applied to a wide range of sites. For example, open-air sites rarely contain preserved bone or features, such as hearths, which were central components to identifying characteristics of site structure. In addition, many of these methods often did not take into consideration the temporal dynamics of the occupation, i.e., that many sites were formed through subsequent occupations of differing duration. This paper proposes the use of two related methods that assume many assemblages are the result of more than one occupation. The methods target the distribution of lithic artifacts, the most ubiquitously preserved of archaeological materials, and accounts for the potential that the final resting place of artifacts was the result of both intentional and unintentional movement by humans and a host of biological and geological processes. The main goal of this paper is to use an understanding of how these processes influenced the formation of site structure to estimate the relative number and duration of occupations for each site in the sample. These new methods will be presented and explained through the study of seven open-air Middle Paleolithic sites in France but are applicable to a wide range of hunter-gatherer sites.  相似文献   
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This article explores the Irish migrant experience in Birmingham during and in the wake of terrorist campaigns carried out in Britain between 1969 and 1975 and attributed to the Irish Republican Army (IRA). Beginning with a discussion of the competencies with which Irishness was associated at the close of the 1960s in England, many of which were hinged on a notion of the Irish predisposition towards violence, the article continues on to take the political, cultural and religious “temperature” of the Irish community in Birmingham between 1969 and 1975, and follows on with a discussion of the specific strategies sought out by Irish immigrants to come to terms with the effect of events such as the “Birmingham Bombings” on their daily lives. Principle findings that emerge from the study indicate that IRA terrorism forced the Irish in Birmingham to engage with and adopt a number of distinct linguistic and cultural strategies in the post-1974 period, the cultivation of which indefinitely altered their relationship with Ireland as “home”, their visibility in the public British sphere and their associational patterns and practices within the migrant enclave.  相似文献   
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Federalism often creates additional decisions for interest groups in determining how best to advocate for their policy recommendations in the legislative process. Should they focus their advocacy at the local, state, or national level of government? This article examines interest group behaviors in water quality policy in the Great Lakes region from 1960 to 2000. I evaluate the reasons for interest group decisions about which level of government to target, using historical analysis of Great Lakes water quality policy in the United States and Canada. The results of this analysis show that in many cases groups are influenced in their decision-making based on the level of government that has the greatest jurisdiction over the policy, supporting a neoinstitutional argument.  相似文献   
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Rock‐magnetic techniques were used to examine the topsoil layer of Kurma archaeological site (in the Olkhon region, on the north‐western coast of Lake Baikal, Siberia) in an effort to determine the possible sources of iron ores for iron‐smelting centres (at about the bc /ad boundary). Measurements have shown a magnetic enhancement of the topsoil due to magnetite grains resulting from weathering of strongly magnetic crystalline rocks. They have also revealed a preliminary picture of the distribution of strongly magnetic topsoils around the ancient iron‐smelting centres. Perhaps, in addition to traditional sources of raw materials, the ancient metallurgists used black sand talus as an ore deposit.  相似文献   
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Thermal–hydrological–mechanical coupling processes suggest that fault permeability should undergo dynamic change as a result of seismic slip. In igneous rocks, a fault's slip surface may have much higher permeability than the surrounding rock matrix and therefore operate as a conduit for fluids. We conducted laboratory experiments to investigate changes in fracture permeability (or transmissivity) of a fault in granite due to shear slip and cyclic heating and cooling. Our experiments showed that high initial fracture transmissivity (>10?18 m3) was associated with a high friction coefficient and that transmissivity decreased during slip. We propose that this reduction in transmissivity reflects the presence of gouge in fracture voids, increasing the area of contact in the fault plane and reducing the hydraulic aperture. In contrast, when initial fracture transmissivity was low (<10?18 m3), we observed that friction was lower and transmissivity increased during slip. The high transmissivity and high friction may be explained by large areas of bare rock being in contact on the slip surface. Slip velocity had little influence on the evolution of permeability, probably because gouge produced at different slip velocities had similar grain size distributions, or because gouge leaked from the slip surface. Transmissivity decreased with increasing temperature in heating tests, probably due to thermal expansion increasing normal stress on the fracture. Frictional heating did not influence transmissivity during the shearing tests.  相似文献   
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