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J. A. Cocilovo H. H. Varela T. G. O'Brien 《International Journal of Osteoarchaeology》2011,21(3):300-312
One of the most interesting issues of the interface between biology and culture is the artificial deformation of the skull. This modification is produced during early morphogenesis through the use of devices that alter the normal growth and development, to obtain a culturally established model. This paper, using a large cranial sample from the South Central Andes (1586 individuals), describes and documents a detailed morphometric study of the changes affecting the vault, cranial base, face, orbits and nasal region resulting from the tabular erect (TE), tabular oblique (TO), circular erect (CE) and circular oblique (CO) deformations with respect to the model without deformation. Data from 17 metric variables were processed by a one‐way ANOVA and LSD test for paired comparisons. All of the deformation types produce significant morphometric divergence in most of the anatomical structures of the skull. The TE exhibits: a restriction of antero‐posterior growth producing expansion in cranial width and height, frontal flattening, shortening of the face and cranial base, widening of the face, increased nasal and orbit height (ORH) and a foramen magnum size increase. The TO exhibits: most change reflected in the widening of the cranial vault, shortening of the cranial base and face, frontal flattening, increased nasal and ORH and foramen magnum size decrease. The CE style exhibits: a decrease in cranial width and strong increase in the cranial height, a reduction in frontal width, expansion of the cranial base and face, increased nasal and ORH, orbital widening and a foramen magnum size increase. The CO style exhibits: a decrease of the cranial vault's width and height, expansion along its length, stretching of the cranial base and face, reduced frontal width, fronto‐malar and biorbitary elongation of the face and further development of foramen magnum. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
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Alan N. Williams 《Journal of archaeological science》2012,39(3):578-589
Using a database of Australian archaeological radiocarbon dates (n = 2996), this paper explores three key methodological issues associated with the use of summed probability plots of radiocarbon data: 1) the minimum sample size needed for a statistically reliable plot; 2) the effect of radiocarbon calibration on the structure of these plots; and 3) the application of a taphonomic correction to such time-series data. The results identify several protocols, recommended as best-practice when using summed probability plots: 1) a minimum sample size of 500 radiocarbon dates should be used, and the sample size and the mean of the standard deviations of the radiocarbon dates (ΔT) in the sample should both be reported; 2) a moving average trendline of 500-800 years should be used to offset the effects of the calibration process; and 3) Surovell et al. “Correcting temporal frequency distributions for taphonomic bias” [Journal of Archaeological Science 36 (2009) 1715-1724] is explored, with modifications and temporal limits (<25,000 cal years BP) proposed. Correction of time-series data using theoretical taphonomic correction curves is useful as a heuristic tool but can obscure real trends if applied routinely. Comparison between summed probability plots and other occupation data is presented and shows good correlation. However it is recommended that plots are supplemented by other archaeological indices and the cross-comparison of such multiple proxies will strengthen identification of occupation trends. 相似文献
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学界关于北宋西北边疆层级体系到底是二级制还是三级制存在分歧,并有许多不够明确的地方。本文认为,北宋边疆层级体系在西北、北方两个方向是由极边、次边、近里构成的三级制。其中,河东路与河北路由于与辽的关系比较和缓,三级制的层级体系相对稳定。陕西路与京东路由于有西夏的和战关系以及女真崛起等因素的影响,尽管仍实行三级制,但其层级体系存在或多或少的变动。总体而言,北宋西北边疆层级体系是一种基于纵深防御理论的边防体系。 相似文献
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ARTAK MARTIROSYAN NIREN BISWAS UTPAL DUTTA DAVID COLE APOSTOLOS PAPAGEORGIOU 《Journal of Earthquake Engineering》2013,17(2):251-274
Understanding the dynamic behaviour of soil in the Anchorage basin in southcentral Alaska is essential for seismic hazard assessment of this highly seismically active region. The analysis of site responses for 40 sites from weak-motion and strong-motion data with amplitudes less than 0.1 g showed a strong influence of subsurface geological conditions on the characteristics of ground motion. Particularly, the sites in the central part of the city, including the downtown area, showed prominent resonance peaks around 1 Hz with amplification values up to about 4. The numerical analysis, based on one-dimensional multi-layer soil models shows that site response characteristics, and especially aforementioned peaks, are largely related to the thick, soft layer of Quaternary deposits, particularly cohesive fades of Bootlegger Cove Formation. The computed transfer functions for soil profiles of six representative sites are in accord with the site responses in the frequency range from 1 to 5 Hz. There is no significant change in amplification values below 2 Hz corresponding to large-amplitude (up to 0.38 g) ground motions; however, above 2-3 Hz the amplification values are greatly reduced in this case. 相似文献
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KOUTEVA MIHAELA∗ F. PANZA GIULIANO ROMANELLI FABIO PASKALEVA IVANKA 《Journal of Earthquake Engineering》2013,17(2):209-229
An approach, capable of synthesising strong ground motion from a basic understanding of fault mechanism and of seismic wave propagation in the Earth, is applied to model the seismic input at a set of 25 sites along a chosen profile at Russe, NE Bulgaria, due to two intermediate-depth Vrancea events (August 30, 1986, M ω=7.2, and May 30, 1990, M ω=6.9). Accordingly to our results, once a strong ground motion parameter has been selected to characterise the ground motion, it is necessary to investigate the relationships between its values and the features of the earthquake source, the path to the site and the nature of the site. Therefore, a proper seismic hazard assessment requires an appro-priate parametric study to define the different ground shaking scenarios corresponding to the relevant seismogenic zones affecting the given site. Site response assessment is provided simultaneously in frequency and space domains, and thus the applied procedure differs from the traditional engineering approach that discusses the site as a single point. The applied procedure can be efficiently used to estimate the ground motion for different purposes like microzonation, urban planning, retrofitting or insurance of the built environment. 相似文献
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This paper studies the effects of soil layering in the basin based on the characteristics of basin-edge induced surface waves and associated differential ground motion. Seismic responses of various basin-edge models were simulated using software based on parsimonious finite difference staggered grid approximation of 2.5D eiastodynamic wave equation. Seismic responses of various models with different number of soil/soft rock layers but for a fixed thickness of deposit, fundamental frequency and impedance contrast revealed a decrease of surface wave amplitude with an increase in the number of layers in the basin. Shifting of dominant frequency towards the higher values was obtained with an increase of number of layers. An increase of dispersion of surface waves with an increase of number of soil layers in the basin was observed. A minor increase of Rayleigh wave velocity with an increase of number of soil layers was also obtained, but in the case of Love wave it was almost negligible. Spectral analysis of the edge-induced surface waves revealed that the anomalous earthquake intensity may arise in a zone of width of 2.5–3.0 km, parallel to basin-edge and at an offset of 0.5–0.7 km from the edge. Maximum horizontal differential ground motion (HDGM) developed by Love wave (≈4.9×10?2) was more than that of Rayleigh wave (≈9.4×10?3). Large variation in HDGM caused by the surface waves was obtained with a change in the number of layers in the basin and maximum HDGM was observed when there were only two layers in the basin. It was inferred that the effect of soil layering in the basin was more on the Rayleigh wave as compared to the Love wave. Development of large HDGM near the basin-edge and its dependency on the number of soil layers reveals that basin-edge induced surface waves need special attention during seismic microzonation or seismic hazard prediction. 相似文献
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In October 1995 an earthquake with a magnitude of 7 on the Richter scale occurred in Sumatra, 450 km from Singapore. Tremors were felt by occupants of several buildings in Singapore and were recorded as an RMS acceleration value by instruments installed in a high-rise condominium. Based on this value and considering instrumental effects, site conditions and building characteristics, this paper investigates the ground motion accelerations and the building response. 相似文献
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Joan Barceló 《Nations & Nationalism》2014,20(4):701-720
Does the interaction between context and individual‐level features affect political attitudes? By using the case of Catalonia, a receiver region of international and national immigration since the fifties, this paper intersects a classic acculturation model and a newly reemerging literature in political science on contextual determinants of political behaviour to analyze how context affects subjective national identity. Results reveal that environment matters. The Percentage of Spain‐born population in the municipality is statistically significant to account for variance in the subjective national identity, even after controlling for age, sex, origin, language and left–right orientation and other contextual factors. This conclusion suggests that researchers should not underestimate the direct effect of the environment on feelings of belonging in contexts of rival identities. 相似文献