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1.
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   
2.
This study examines possible morphological variation in the knee joint of Homo sapiens with increasing age in ostensively healthy and non‐pathological distal femora and proximal tibiae. Throughout the lifetime of each individual, the hard tissue of the knee undergoes considerable remodelling as a response to biomechanical stresses, changes in bone microarchitecture and reduction of bone mineral content as a concomitant of ageing. The knee is also subject to greater levels of degenerative joint disease than any other joint. If death occurs whilst such diseases are in the earliest stages, initial bone changes may not be visually obvious in museum specimens. If such specimens are used for comparative analyses, it is hypothesised that changes might render it problematic if all ages are conglomerated into discrete samples. This study therefore investigates the degree to which the distal femur and proximal tibia change shape during ageing and, if changes are present, whether they are expressed similarly in males and females. It also examines whether changes are of greater magnitude than those morphological differences which might exist between populations. In an example population of African‐Americans, results indicate that there is a statistically significant difference in shape between age groups and those differences become progressively greater between the youngest and oldest adults. Results also show that although morphological variation caused by ageing is apparent, those shape differences attributable to sexual dimorphism are more powerful. When two additional populations are analysed jointly with the African‐Americans (Caucasian Americans and the European Spitalfields sample), results indicate that inter‐population shape differences are considerably greater than differences caused by increasing age. Results imply that it is justifiable to combine specimens of all ages into discrete samples for comparative purposes. Copyright © 2007 John Wiley & Sons, Ltd.  相似文献   
3.
In this paper, the conception of .Great Britain. — a wholly unsatisfactory nomenclature — as an island nation is examined. In this case, a relatively small land mass acted as an originary point of departure for outward‐bound Great Power projections across the open spaces of seas. This paper further explores the varied implications for nationalism within Britain of the diverse island ‘roots’ of the British navel and the ‘routes’ of British navalism. Three themes recur in the popular mobilization of British maritime island nationalism: the besieged island, the island as universal exemplar of civilization, and the navy as national protector. Some consideration is given to the significance of island symbols such as Britannia as a marker of the fate of great island nationalism.  相似文献   
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In some shipwrecks we can recognize factors such as units of measurement, use of segments and arcs, and repetition of shapes, which may have been rationalised during the transition from craft shipbuilding to a formal design process. This is an a posteriori assessment, as we do not know how hull‐shapes were planned and controlled in Antiquity. However the Cheops boat, and the Madrague de Giens, Anse des Laurons II, Fiumicino 4 and Yassi Ada II wrecks, display measurements and geometries suggesting rational approaches to hull‐moulding, with principles common to those of medieval and Renaissance shipbuilding and the traditional Mediterranean garbi. © 2012 The Author  相似文献   
6.
Many qualitative and quantitative methods for the separation of sheep and goat bones are based upon Middle Eastern, Mediterranean and European specimens. However, these methods may not be as applicable in other geographical contexts due to regional morphological variation. In order to address this, both traditional and geometric morphometric methods were applied to sheep, (Ovis aries L.) and goat (Capra hircus L.) astragali from archaeological sites from Kazakhstan dating to the Late and Final Bronze Age (1900–900 bce ). This exploratory research confirmed that qualitative features remained useful for distinguishing between species, while traditional morphometric methods were unable to conclusively support the field identification of species. Geometric morphometric methods found significant morphological differences between species and confirmed group membership while exploring specific qualitative features that were effective in distinguishing between sheep and goat in Central Asian contexts. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   
7.
It is well known that local soil conditions play a key role in the amplification of earthquake waves. In particular, a liquefiable shallow soil layer may produce a significant influence on ground motion during strong earthquakes. In this paper, the response of a liquefiable site during the 1995 Kobe earthquake is studied using vertical array records, with particular attention on the effects of nonlinear soil behaviour and liquefaction on the ground motion. Variations of the characteristics of the recorded ground motions are analysed using the spectral ratio technique, and the nonlinearity occurring in the shallow liquefied layer during earthquake is identified. A fully coupled, inelastic finite element analysis of the response of the array site is performed. The calculated stress-strain histories of soils and excess pore water pressures at different depths are presented, and their relations to the characteristics of the ground motions are addressed.  相似文献   
8.
Principal Components Analysis (PCA) of measurements on twelve metacarpal and ten metatarsal dimensions indicates that metapodials differ much more in size than in shape among the twenty-three genera of extant Sub-Saharan bovids. The only conspicuous shape variation is in metapodial length, which sometimes differs significantly among genera that are similar in all other dimensions. It follows that Discriminant Analysis (DA) intended to identify metapodials to genus will depend primarily on size, and except for the occasional like-sized genera that differ in metapodial length, DA will often confuse genera of similar size. DA of the same metapodials subjected to PCA supports this prediction. PCA further shows that bovid species that favor the same habitat often differ in metapodial size, shape, or both, and species that favor different habitats often overlap substantially in their metapodial morphometrics. DA intended to assign metapodials to habitat will thus produce different results depending on the species used to characterize each habitat type and on the number of specimens by which each species is represented. Habitat reconstruction founded in DA is therefore taxon dependent rather than taxon-free, and it cannot supplant reconstruction based on taxonomic identifications below the family level.  相似文献   
9.
The analysis of the archaeological remains of ships and boats, in particular hull shapes, have been central to wider analysis of performance, function, and significance within past societies. This article reviews established methods of quantifying shape in ship and boat archaeology—linear measurement ratios and form coefficients—and evaluates the utility of 3D geometric morphometrics (GM). The 3D shape of 30 vessels from north‐west Europe dating between 325 BC and AD 1915 are quantified to study how hull shape relates to a vessel's function and intended operating environment. A comparison of the three methods highlights the importance of analysing the complexity of a hull in a holistic manner and demonstrates that 3D GM outperforms the traditional methods.  相似文献   
10.
Over the last four decades, there has been surprisingly little advance in the quantitative morphometric analysis of Palaeolithic stone tools, especially compared to that which has taken place in biological morphometrics over a comparable time frame. In Palaeolithic archaeology's sister discipline of palaeoanthropology, detailed quantitative morphometric, geometric morphometric, and even 3D geometric morphometric analyses are now seen almost as routine. This period of relative methodological stasis may have been influenced by the lack of homologous landmarks on many lithic tools (essential for any comparative analysis), especially core-based technologies of the Lower Palaeolithic. Archaeological field conditions may also prohibit the use of expensive and delicate precision instruments in certain cases. Here we present a crossbeam co-ordinate caliper that – crucially – both geometrically locates and measures distances between morphologically homologous landmarks upon lithic nuclei via a single protocol. Intra- and inter-observer error tests provide evidence that error levels associated with the instrument fall within acceptable ranges. In addition, we present empirical examples of application in the form of a multivariate analysis of 55 discrete morphometric variables, and a 3D geometric morphometric analysis of co-ordinate landmark configurations derived from Pleistocene lithic nuclei (i.e. ‘cores’ sensu lato). We also introduce to lithic studies some techniques for the study of shape variation that have previously been used with success in biological morphometric analyses. We conclude that use of an instrument such as the crossbeam co-ordinate caliper may provide a useful adjunct to traditional techniques of lithic analysis, particularly in developing a quantitative morphometric approach.  相似文献   
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