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The La Gila Encantada Site is located on an isolated ridge top north of Silver City, New Mexico in an area defined culturally as the Mimbres Mogollon region. The 180 m × 80 m (14400 m2) sized site was originally recorded as a dense scatter of ceramics, lithics, and ground stone along with a number of surface depressions that appear to represent pithouses. Cesium magnetometer surveys were conducted to identify hearths, pithouse boundaries, and activity areas outside of pithouses in support of archaeological investigations, and to test this instrument's ability to image these features. This paper presents a characterization of the magnetic signature of a pithouse as a magnetic high in the center caused by the central hearth, low magnetic variability along the floor of the house, and then increased magnetic variability at the pithouse boundary. This characterization was successfully confirmed for three pithouses using cesium magnetometery and archaeological excavation.  相似文献   
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One of the key aims of the Dunedin Southern Suburbs project has been to examine the factors that structured opportunity in a period of rapid modernization in New Zealand, 1880-1940. This article argues that health was a key determinant of opportunity and examines how people thought about their bodies and sought to maintain health. It argues that older, humoral theories about health were maintained alongside new understandings wrought by the germ theory and that both placed a high value on regimen. Mothers were regarded as the household experts on health but lacked a vocabulary to communicate with their daughters about menstruation. While bodily health was an ideal to be striven for, there was little communication about bodily pleasure, a situation subject to change with the adoption of family limitation.  相似文献   
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Tests for differences among regional means are typically carried out by analysis of variance (ANOVA). When such data are spatially autocorrelated (SA), the assumptions of ANOVA are not met, giving rise to excessive type I error rates. Two spatially adjusted ANOVA methods, Griffith's and COCOPAN, have been proposed to overcome this problem. In this study we show, by means of extensive simulations, the magnitude of the error rates introduced by SA induced in isolation-by-distance models typical of those used in population genetics. For data suspected of exhibiting such SA, we propose a strategy for distinguishing between inherent SA, generated within the data by a contagious process, and spurious SA, introduced by regional differences in means. The approach adopted is that of restricted randomization of distance matrices. We also furnish error rates and power estimates for both Griffith's method and COCOPAN. In addition to the simulated data, the methods are applied to an actual example from plant population biology.  相似文献   
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