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101.
Ya-Qin Hu Zhong-Li Zhang Subir Bera David K. Ferguson Cheng-Sen Li Wen-Bin Shao Yu-Fei Wang 《Journal of archaeological science》2007
The provenance of more than 2200-year-old terracotta warriors and horses in the Qin Shihuang Mausoleum is still a mystery, even though some researchers have inferred that the terracotta figures were produced near the mausoleum. The sporomorphs (pollen and spores) extracted from terracotta fragments of a warrior and a horse and compared with those obtained from soil samples from the Qin Dynasty layer in Pit No. 2 of the Qin Shihuang Mausoleum indicate that the pollen spectrum from the terracotta horse is different from that of the warrior, but similar to the local soil samples. Herbaceous pollen was dominant in the warrior sample, while arboreal pollen predominates in the horse and soil samples. Palynological evidence suggests that the terracotta horses were produced at a locality near the mausoleum, while the warrior came from a site which was further afield. 相似文献
102.
103.
Increasing Role of Services in Competitive Power and Innovativeness of Firms and Industrial Clusters
The aim of this paper is to discuss the importance of different types of global services for industrial firms and clusters in terms of their economic competitiveness and innovative performance. The theoretical debates argue that globalization, deregulation and the new production organization make it necessary to use global services that are supplied easily with the help of new telecommunication technologies. The existing empirical studies provide some supporting evidence. However, they also indicate that global service firms can be attained by only smaller numbers of industrial firms and clusters. Still, in-house services besides temporal and informal mechanisms are important to meet the needs of the specialized services, even for the firms that try to become a part of the global production system. The paper focuses on three main questions: “What types of global services are becoming crucial for manufacturing firms and what type of services are still local and national? Is there a significant difference between the characteristics of firms that use the same type of services? To what extent is having access to global services important for the innovativeness of industrial firms and clusters? This paper looks for the answers to these questions based on existing case studies as well as this study of three industrial clusters in Turkey. The findings indicate that there is not a perfect match between theory and empirical evidence and there is a need for more refined theoretical discourses on industry–service relations. 相似文献
104.
Ashok K. Behuria 《Australian Journal of International Affairs》2007,61(4):529-543
Some new groups calling themselves Pakistani Taliban with links to the Afghan Taliban have asserted themselves in the tribal areas of Pakistan. This has complicated the internal security scenario for Pakistan. This article traces the roots of the problem and argues that the State with its confessional character emits strong Islamist impulses making it easy for Taliban-like forces to take roots in Pashtun dominated areas in Pakistan. While the process of Talibanisation may not succeed in engulfing the entire state of Pakistan, it will certainly pose a critical internal challenge, contributing to its fragility and compelling Pakistan to stay perennially engaged with its internal security. Roll back is difficult but not impossible. This will involve the strong commitment of the State to take steps to bring about social, economic and political transformation in the Taliban-infested areas, and an effort on the part of the international community to help Pakistan in this critical endeavour. 相似文献
105.
Granitoid (pegmatite and aplite) veins in metamorphic rocks and intrusive syenites of central Dronning Maud Land, Antarctica, are flanked by conspicuous light‐coloured alteration halos, which represent the damage zone of fracture propagation. The damage zone is characterized by a high density of sealed or healed microcracks, about 1 order of magnitude above background. Fluid inclusions along healed microcracks in quartz of both pegmatite and alteration halos are inspected by optical and scanning electron microscopy, and their composition is analysed by microthermometry and quadrupole mass spectrometry. The similar inclusion record in the granitoid vein and in the damaged host rock indicates the derivation of the fluids from the hydrous melt phase. The aqueous inclusions bear abundant daughter crystals, mainly silicates, and may represent a hydrous melt. The volatile composition is variable in the system H2O–CO2, with mostly subordinate amounts of N2. Phase separation with partitioning of CO2 into the fluid phase coexisting with the hydrous melt, and possibly immiscibility in the subsolidus range, govern fluid evolution during cooling. The variable CO2/N2 ratio suggests mixing with fluids from an external source in the host rock and vigorous circulation at an early stage of high transient permeability. Experiments have shown that healing of microcracks at high temperatures is a matter of hours to weeks, hence similar in time scale to the cooling of the cm‐ to dm‐thick granitoid veins. In this case, rapid cooling and concomitant crack healing in a system undergoing phase separation causes a broad compositional variability of the inclusions due to necking down, and the underpressure developing in closed compartments precludes a meaningful thermobarometric interpretation. 相似文献
106.
The generation of computational meshes of complex geological objects is a challenge: their shape needs to be retained, resolution has to adapt to local detail, and variations of material properties in the objects have to be represented. Also mesh refinement and adaptation must be sufficient to resolve variations in the computed variable(s). Here, we present an unstructured hybrid finite element, node‐centred finite‐volume discretization suitable for solving fluid flow, reactive transport, and mechanical partial differential equations on a complex geometry with inhomogeneous material domains. We show that resulting meshes accurately capture free‐form material interfaces as defined by non‐uniform rational B‐spline curves and surfaces. The mesh discretization error is analysed for the elliptic pressure equation and an error metric is introduced to guide mesh refinement. Finite elements and finite volumes are represented in parametric space and integrations are conducted numerically. Subsequently, integral properties are mapped to physical space using Jacobian transformations. This method even retains its validity when the mesh is deformed. The resulting generic formulation is demonstrated for a transport calculation performed on a complex discrete fracture model. 相似文献
107.
K. A. Plomp C. A. Roberts U. Strand ViarsdÌttir 《International Journal of Osteoarchaeology》2015,25(4):515-527
Osteoarthritis is a major health concern in living populations, as well as being one of the most common pathological lesions identified in the archaeological record. The aetiology of the disease remains unclear, with a multi‐factorial influence of physical strain, age, genetics, and obesity. Previous studies have identified a relationship between the presence of knee osteoarthritis on the distal femoral joint and the morphology of the intercondylar notch, patellar groove, and medial condyle. The current study expands this research to investigate the relationship between distal femoral, distal humeral, and proximal ulnar joint morphology and osteoarthritis with 3D shape analysis techniques. These methods provide a more detailed analysis of joint morphology in order to determine any relationship between 3D shape and osteoarthritis. The results indicate a complex relationship between joint shape and knee osteoarthritis, with eburnated right femora showing a statistically significant association. The shapes associated with eburnated or affected femoral joints can be explained by osteophyte development, and therefore likely represent systematic shape changes and not a particular joint shape predisposing individuals to the condition. There was no identifiable relationship found in the proximal ulna or distal humerus, indicating that joint shape is unlikely to influence the development of the condition in the elbow joint and that any shape changes produced by osteoarthritis are not systematic or quantifiable. The joints analysed in this study were highly influenced by asymmetry, sexual dimorphism, and allometry, resulting in a small sample size of affected joints in many datasets. Further analyses of large skeletal samples are needed to more thoroughly investigate the possible relationship of distal femoral joint shape and osteoarthritis. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
108.
Palaeohistology as a valuable diagnostic instrument is dependent on the production of high‐quality thin‐ground sections from dry bone. The objective of this study was to consider technical differences and assess the qualitative outcomes of five techniques for preparing thin‐ground sections from dry archaeological bone. Established techniques with long follow‐up times and excellently documented results were compared with simpler and cheaper time‐saving techniques. Evaluations were made of the quality of thin sections obtained by one classical machine‐based embedding technique, two revised versions of the same technique, one manual moulding technique based on Frost's rapid technique and one manual hybrid technique. Five osteological specimens of differing quality were prepared following the manuals for these five techniques and examined microscopically with respect to a list of standardised histological and diagenetic parameters. Alterations in the specimens attributable to preparation effects were recorded, and observations were scored with reference to three criteria: section quality, technical quality and staining. The results show that embedding techniques are to prefer. Superglue should not be used as a mounting or embedding medium. Manual grinding comes with several limitations, and machine cutting and grinding are preferred. Haematoxylin staining can be successfully applied to embedded specimens, giving more information on microscopic diagenetic processes. A stepwise manual for a revision of the classical embedding technique is presented. The time required for producing sections using classical embedding techniques is shortened from 6 weeks to 3.7 days by refining the preparation/polymerization processes involved with no loss of osteological data. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
109.
A biological object was recovered from the pelvic region of an adult woman coded to SK13 unearthed from Oluz Höyük in Amasya, Turkey. The skeleton was dated to the medieval period on the basis of the burial customs and the calibrated 14C dates. The find was identified as a bladder stone on morphological, radiographic and chemo‐analytical grounds with the help of X‐ray diffraction, polarised energy dispersive X‐ray fluorescence spectroscopy, confocal Raman spectroscopy, and microscopic techniques. The mineralogical composition of urinary stone was found to be as calcium phosphate (apatite). Bladder stone disease is endemic in poor agricultural regions where the typical diet is mostly based on grain carbohydrate consumption with scarce intake of animal protein. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
110.
Archaeological experiments that use modern bones to replicate past animal bone assemblages have often failed to consider the effects of environment, storage and preparation on modern bones. Often, these experiments make little mention of the conditions to which bones were subject during their storage and preparation for use in experiments. In other instances, these variables are reported but not considered as factors that contribute to the nature of the results obtained. This study considers previously reported data concerning the degradation of frozen bones (−20°C), and bones exposed to hot, dry conditions (40°C), and presents new data for bones exposed to room temperature environments (22°C) and refrigerated environments (2°C), and bones that are frozen (−20°C) and then thawed (22°C). These conditions are all relevant to understanding the nature of bone degradation and the use of bones in modern archaeological experimentation. This article also surveys a range of previously reported experiments that utilise modern bones to create analogies to the past and considers different methodological approaches and their relationship to the condition of bones at the time of their fracture and fragmentation. The longitudinal data presented in this study demonstrate differential rates of bone degradation over time in various environmental conditions. This degradation results in dramatic changes in bone fracture morphology, bone strength and utility for bone tool production. These observations have significant implications for experiments that utilise modern bones, especially when experimental data are used to create analogies to the archaeological past. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献