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The evolution of habitual terrestrial bipedalism in the ancestor of the Hominidae can be reconstructed through an examination of historical transformations of shared-derived morphological-behavioural complexes related to bipedalism in catarrhines. This reconstruction indicates that terrestrial bipedal displays may be of particular importance in understanding the development of habitual terrestrial bipedalism because they are the most recently acquired morphological-behavioural characteristic shared by the African great apes and humans. We suggest that in the late Middle and Late Miocene of East Africa, as habitats were becoming more open and desiccated and resources more widely separately, increased competition for resources ensued. We propose that the adoption of bipedal displays were the behaviours essential to the success of pre-hominids in this environment in that they allowed for the relatively peaceful resolution of, firstly, intragroup and, eventually, intergroup conflicts. It is hypothesized that the widespread use of bipedal displays for social control in pre-hominids reduced a major source of morbidity and mortality. Bipedal postures, once adopted for social control, probably became common elements of the pre-hominid postural repertoire. With time, this new pre-adaptation to upright standing would have facilitated a multifactorial development of fully habitual terrestrial bipedal locomotion.  相似文献   
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The Indian peoples of the Cuchumatán highlands of Guatemala, like their counterparts throughout Spanish America, were forced to render labour to their European conquerors in a variety of ways. Foremost among the institutional devices which controlled and exploited native labour were the encomienda, the tasación de tributos, and the repartimiento. Prominent and prestigious chiefly during the first century of colonial rule, the encomienda was a means whereby a privileged individual was granted the right to enjoy the tribute, and originally also the labour, of a certain number of Indians in a designated town or group of towns. The amount of tribute owed by a town was stipulated by the tasación de tributos, which assessed tribute-paying capacity principally in terms of age, sex, and marital status. Through the operation of repartimiento, labour was coerced from the Indians and channelled into a number of menial and servile tasks. During the eighteenth century, debt peonage was a further means of securing a work force in the Cuchumatán highlands, particularly on the large haciendas which dominated the commercial agricultural economy of the region.  相似文献   
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Kuwait–Georgian archaeological work at Failaka Island showed the need for geological study. Analysis of sediments related to drinking water-collecting cisterns was performed on a Late Islamic settlement (NE part of the island) in 2018. Field sedimentological, grain size and XRD analysis of the sediment profiles showed that the shallow (about 1 m deep) cone-shaped wells are dug in the loose, porous, cross-stratified calcareous coarse-grained quartz sandstones. Three upper layers of quartz sandstones in the profile have high infiltration rate and provide a rare yet ideal material for water retention. The fourth dense layer below, composed of very fine sand and silt fraction, tends to hinder water movement and forms a relatively impermeable water-resistant surface. Thus, the distribution patterns of clay content, grain sizes and porosity of the well-hosting sediments are favourable for freshwater infiltration and harvesting. An additional petrographic analysis was conducted on different types of rocks discovered on the archaeological site, used as building material and fragments of stone artifacts to identify their origin. It was established that archaeological building material is of local origin, whereas the source rocks for stone artifacts were imported.  相似文献   
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Numerous Hellenic terms have been gradually adopted during the development of modern medical science. Moreover, there are a significant number of words that derive directly from the Hippocratic texts. Hippocrates (ca. 460-ca. 377 BC), revered as the father of medicine, and his followers left behind a valuable heritage of medical knowledge that, practically, laid the foundations of Western medicine. Their theories, collected in Corpus Hippocraticum, transformed medicine by adding, mainly, clinical observation and inductive reasoning as significant parts of medical diagnosis and treatment. Additionally, Hippocratic writings have provided an invaluable heritage of medical terms for all medical fields. The present article examines the Hellenic and Hippocratic terminology referring to the spine and how this vocabulary has influenced and dominated upon modern spinal onomatology.  相似文献   
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A method for investigating the forming technique of ancient ceramic vessels is presented. The recording, analysis, and comparison of the vessels' metrical properties by means of computer tomography, three-dimensional laser scanning, and solid-modeling software enables the identification of the applied manufacturing methods. A finite elements method-based simulation of the developed deformations during the vessels' manufacture offers significant insight into the applied shaping procedures. By making possible the exact recording of both the internal and external form of the vessels as well as the simulation of the forming procedure, the method represents a marked improvement to hitherto applied methods based on radiography. The method is applied on two early iron age ceramic jugs (oinochoai) found as offerings in tombs in excavations in Dion, Greece.  相似文献   
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