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Portable X-ray fluorescence (pXRF) instruments have gained considerable attention within the archaeological community. Few other recent instrumental developments have generated such debate. Much of this debate, which is dominated by scepticism over analytical performance, has occurred in informal settings. Rather than judge the use of pXRF based on unpublished work and conference banter, we conducted an extensive literature review of peer-reviewed research that used this technology. Our focus is developing an understanding of how, where, and why pXRF is being used in archaeology. What interests us most are research designs into which only pXRF could be integrated and the new research approaches these instruments may facilitate. Trends that emerged from the literature are surprising. For example, only 43% of the archaeological “pXRF” papers actually involve handheld instruments. In addition, more than four-fifths of handheld pXRF in archaeology is apparently conducted in laboratory contexts. Only 3% has been conducted in a fieldhouse or on-site laboratory, and 15% at an excavation, on a survey, or inside a historic structure. Here we argue that, while the technical capability to analyse archaeological materials using portable instruments may exist, it is not necessarily true the methodological and theoretical frameworks are in place to allow such activities to be archaeologically successful and significant. Because handheld pXRF is uniquely suited to in situ analysis, we expect the first changes in methodological and theoretical approaches will involve space, context, and related frameworks. 相似文献
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U.S. immigration policy has been the subject of considerable debate in recent years. Previous research has focused on how temporal variation in federal policy has altered the migratory behavior of immigrants. The effect of spatial variation in enforcement remains untested. Relying on the criminological distinction between general and specific deterrence, we argue that high rates of enforcement are unlikely to encourage undocumented immigrants to self‐deport. We also examine the effects cultural and economic immigration policies adopted by the states. Previous research suggests that migrants will choose to remain in states with favorable environments, but this claim has not been directly tested. We draw on data from the Mexican Migration Project (MMP) to address these gaps. MMP data are supplemented with government data on federal enforcement obtained from Immigration and Customs Enforcement (ICE) and measures of state policy. Our findings suggest that higher rates of enforcement and the establishment of negative policy environments do not encourage undocumented immigrants to leave the United States at a higher rate than their documented counterparts do. Rather, high enforcement contexts exaggerate the differences between documented and undocumented migrant behavior, with undocumented migrants staying longer. Liberal state policies have no discernible effect. 相似文献
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Steven P. Ashby 《考古杂志》2014,171(1):151-184
Personal appearance in general—and the grooming of hair in particular—has long held a position of interest in historical, art-historical, and literary scholarship. The same cannot be said of archaeology, and the material aspects of personal grooming in the construction and communication of identity have not been fully synthesized. As a result, little attempt has been made to understand the social role of hair in less well documented societies, such as those of early medieval northern and western Europe. This paper considers archaeological, iconographic and documentary evidence for the significance of, and physical engagement with hair in early medieval northern and western Europe, and offers a model for the interpretation of grooming as a social phenomenon. It is argued that grooming was a socially meaningful practice, and that it played a key role in the construction of early medieval identities, as well as in the maintenance and manipulation of boundaries and distinctions between individuals and groups. 相似文献