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A small pit in the articular surfaces of the third tarsometatarsal joint has been noted with particularly high frequency in North American Indians. This pit varies in depth, and covers most of the inferior third of the articular surfaces of the third metatarsal and the lateral cuneiform; it is accompanied by remodelling of the inferior surfaces of the bones involved. In the present study, patterns of occurrence are examined in a prehistoric skeletal population from west-central Illinois. This population is extremely well preserved, enabling a thorough examination of feet as well as hands for most individuals. The sample included 496 adults and juveniles above the age of 6 years. Of this total population, 18 per cent exhibit the variation, which occurs more frequently in females and is unrelated to size. Furthermore, 29 per cent of the individuals in which it occurs exhibit this variant only unilaterally, with no significant side differences. Various lesions, trauma and acquired or activity-related aetiologies are explored, as are the patterns of sex association, occurrence near an area of ligamentous attachment and lack of age and size association. It is hypothesized that a discrete genetic trait is represented in the third tarsometatarsal joint of this population in the form of an anomalous interosseous plantar ligament. © 1997 by John Wiley & Sons, Ltd. Int. J. Osteoarchaeol., 7 : 124–132 (1997) No. of Figures: 3. No. of Tables: 2. No. of References: 26.  相似文献   
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NATO's future is again the subject of speculation and debate despite its having fought a recent and apparently successful war in Kosovo. This article proposes that there are three aspects to this challenge. First, NATO is facing a series of dilemmas in its relations with non‐members: how should it manage relations with Russia, and with the applicants for membership? The authors argue that NATO should seek to develop a consolidationist posture. The second challenge is that of developing an EU–NATO partnership in the light of the Helsinki Headline Goals. This, it is proposed, can be developed through a division of labour. The third task, that of military restructuring, is overshadowed by the complexities of processing a working European military structure. In conclusion, the authors suggest that a strategy for the alliance, a key component of the Cold War, but subsequently lost, can be refashioned from the above elements.  相似文献   
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A variety of data indicate that the Carbonate aquifer in southern Manitoba is a heterogeneous and anisotropic aquifer wherein groundwater flow follows preferred flow path networks. Specific capacity tests show that aquifer transmissivity can vary by up to four orders of magnitude within 1 km. Geostatistical analysis reveals a strong anisotropy in the transmissivity field, with better spatial continuity in NE–SW and NW–SE directions, coincident with the dominant orientations of fractures observed in bedrock exposures. However, discrepancies between the orientation of highest fracture density and best transmissivity continuity suggest that either additional geological factors control the preferred flow network or there is a biased representation of the fracture pattern because all direct fracture observations came from the northern part of the study area. In an effort to investigate whether the geographically biased fracture data set represents the fracture pattern for the whole region, Landsat images and digital elevation maps were processed to extract linear features that may indicate subsurface fracture zones in areas where bedrock is covered by glacial sediments. The results suggest a consistent fracture pattern throughout the study area, indicating that the two observed fracture groups might have gone through different processes in terms of permeability development. Alteration by mineral cementation and dissolution along fracture surfaces may have preferentially improved the fracture permeability in one orientation, while reducing it in the other. The in situ stress field is also believed to play a major role in the preferred regional flow network. This paper discusses the evidence for the preferred flow path network and possible geological factors controlling aquifer anisotropy in this region.  相似文献   
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The ‘Southeast Asian Lead Isotope Project’ (SEALIP) is intended to provide reliable geochemical proxies for late prehistoric through early historic (2nd/1st millennium BCE and 1st millennium CE) local, regional, and inter-regional social interactions, in an archaeological arena lacking established ceramic typologies with which to cross modern national boundaries. We present lead isotope characterisations of the three currently known Southeast Asian prehistoric primary (mining/smelting) copper production centres: Phu Lon and the Khao Wong Prachan Valley in Thailand, and the recently discovered Xepon complex in Laos. Kernel Density Estimation shows that these production centres can be clearly distinguished isotopically, as such fulfilling the core tenet of the ‘Provenance Hypothesis’ (Wilson and Pollard, 2001: 508) and permitting SEALIP to proceed as a research programme tracing regional copper/bronze/lead exchange and provenance patterning. In addition we provide a provisional technological reconstruction of copper smelting processes at Phu Lon to complement our more established understanding of the Khao Wong Prachan Valley. Combined lead isotope and technological datasets allow us to tentatively identify trends in the evolution of Southeast Asian metal technologies and of regional social perceptions of metal exchange.  相似文献   
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The mycobacterial cell wall is consists of several long chain lipid and glycolipid components. Mycolic acids are major and unique fraction of the cell envelope of mycobacteria that include the ancient causative agents of tuberculosis and leprosy. The analytical investigation of these lipid biomarker residues is one of the most promising perspectives in the field of molecular paleopathology. Recently published in this journal, Minnikin et al. present a systematic critique of the MALDI TOF MS analysis for determination of ancient mycolic acids, focusing on our previous paper. In this study, our mass spectrometric investigations by commonly used 2,5 DHB matrix were presented with our comments to the critique authors. On the base of our previous and recent mass spectrometric results we have to realize that the clinical protocols and standards cannot directly be used for the biomolecular paleopathological investigations. The applicability of the recent mycobacterial and clinical results is very limited in the biomolecular archaeology, thus the recent scientific results and protocols should be adapted carefully to bioarchaeological sciences.  相似文献   
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