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1.
Tarsal coalition is a congenital defect that results when adjacent tarsals fail to separate properly during embryonic development. Anatomically, coalitions present as non‐osseous bridges of cartilage or fibrocartilage – and occasionally as osseous bridges – between two neighboring bones. In skeletons, non‐osseous tarsal coalitions are recognizable as matching lesions between two bones at predictable locations. These coalitions are of interest because they are known to be heritable and are therefore useful for tracing genetic relatives in archaeological cemeteries, because they can be misinterpreted in skeletons as trauma or joint disease, and because they can result in associated pathology. However, despite a considerable literature on tarsal coalition, estimates of coalition frequencies disagree considerably, perhaps due to biases inherent in clinical sampling. In order to gain a better estimate of tarsal coalition frequencies in human populations, data were gathered on 342 European‐Americans from the Terry Collection (Smithsonian Institution), 536 South Africans from the Dart Collection (University of Witwatersrand, South Africa), and 756 medieval Danish skeletons (Anthropological Database, Odense University). The Danish skeletons are archaeological, with sample sizes by coalition type ranging from 366–507 individuals. Examples of eight different types of intertarsal coalition were identified among the 1634 skeletons examined. Overall frequency estimates for tarsal coalition ranged from 2.1%–3.5%. South Africans exhibited significantly higher frequencies in the midfoot, with naviculocuneiform I coalition (1.0%) the most common type. Conversely, no coalitions of the midfoot were found among the Euro‐Americans or medieval Danes. Instead, these groups exhibited calcaneonavicular coalition as the most common type in the hindfoot (2.0% and 2.1% respectively), while calcaneonavicular coalition was among the least common in the South Africans (0.2%). Copyright © 2010 John Wiley & Sons, Ltd.  相似文献   

2.
This paper reports articular surface defects detected in three foot bones. These were exhumed from Portuguese collective burial places, Hipogeu de São Paulo II (artificial cave, Almada) and Necrópole da Serra da Roupa (shelter, Columbeira) dated to the Late Neolithic and Chalcolithic periods. Other aetiologies were presented, but non‐osseous calcaneonavicular coalition proved to be the most probable explanation for the unusual morphology detected in two calcanei and one navicular bone. Copyright © 2005 John Wiley & Sons, Ltd.  相似文献   

3.
The study of developmental abnormalities of the tarsal bones in a Portuguese Late Neolithic population was performed, as part of an ongoing research project that includes the evaluation of foot defects in Portuguese skeletal populations from Neolithic times to modern 20th century samples. Two accessory bones were found, calcaneum secundarium and os trigonum, and three non‐osseous coalitions were detected, calcaneonavicular, cuboid‐navicular and third metatarsal‐third cuneiform. The newly presented frequencies corresponded to other published sources, except for the frequency of calcaneum secundarium, higher than in previous studies (8.6% left bones; 15.2% right bones). This result suggests population homogeneity maybe due to geographic isolation and/or marriage customs although the exact pattern of inheritance of the majority of these foot anomalies is unknown. No apparent sex bias was detected and side could not be tested since these human remains were uncovered from a commingled funerary context. Copyright © 2010 John Wiley & Sons, Ltd.  相似文献   

4.
Spondylocarpotarsal synostosis syndrome (SCT) is a rare genetic disease. It was described for the first time during the 1970s. The most relevant pathognomonic skeletal changes are vertebral malsegmentation and the fusion of the carpal and tarsal bones. This last implication can be absent in some cases. We have investigated a case of SCT in a female of about 40–45 years of age, dated to the 2nd century ad . This discovery is important for two reasons: first, SCT is not a recent disease but rather one with a very long history; second, the clinical picture of the skeletal changes (malsegmentation of some elements of the spine, fusion of carpal bones) seems not to have varied in the last 2000 years. Furthermore, the age of the Roman female shows medium–long survival in patients suffering from SCT, even in the absence of medical treatment. Copyright © 2011 John Wiley & Sons, Ltd.  相似文献   

5.
How does major policy change come about? This article identifies and rectifies weaknesses in the conceptualization of innovative policy change in the Advocacy Coalition Framework. In a case study of policy belief change preceding an innovative reform in the German subsystem of old‐age security, important new aspects of major policy change are carved out. In particular, the analysis traces a transition from one single hegemonic advocacy coalition to another stable coalition, with a transition phase between the two equilibria. The transition phase is characterized (i) by a bipolarization of policy beliefs in the subsystem and (ii) by state actors with shifting coalition memberships due to policy learning across coalitions or due to executive turnover. Apparently, there are subsystems with specific characteristics (presumably redistributive rather than regulative subsystems) in which one hegemonic coalition is the default, or the “normal state.” In these subsystems, polarization and shifting coalition memberships seem to interact to produce coalition turnover and major policy change. The case study is based on discourse network analysis, a combination of qualitative content analysis and social network analysis, which provides an intertemporal measurement of advocacy coalition realignment at the level of policy beliefs in a subsystem.  相似文献   

6.
Developmental anomalies of the skeleton are often treated as mere curiosities, but in some contexts, they may prove useful to bioarchaeologists for answering questions about the past. One such use can be found in skeletal kinship analysis, where discrete traits can help to identify close genetic relatives in archaeological cemeteries. Previous research suggests that discrete traits used for skeletal kinship analysis should have several characteristics—they must obviously be heritable, but in addition, they should be easy to score as present or absent, their frequencies should not vary by age or sex, and they should be low frequency traits. Low frequency traits are less likely than higher frequency traits to be found in two individuals merely by chance. In this study, we consider 17 developmental anomalies of the human foot as candidates for use in skeletal kinship analysis. The traits are evaluated in terms of the characteristics described above, after which kinship analyses are attempted on two different populations. Ten of the anomalies are found to be good candidates for skeletal kinship analysis, including accessory navicular, four different forms of brachydactyly, three types of tarsal coalition, and two forms of the os intermetatarseum. When frequencies of these traits were examined and compared to a reference sample in three cemeteries, however, only a single group of six possible genetic relatives were identified. The results suggest that skeletal kinship analysis using individual heritable traits is perhaps best applied to small cemeteries or burial clusters rather than larger cemeteries containing many different lineages. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   

7.
An often cited statement in the medical literature is that nine Inca mummies (c.400 bc ) had skin and osseous lesions from melanoma. However, a review of the pattern and type of osseous lesions exhibited by these individuals and the age of at least one of them indicate the data are inconsistent with a diagnosis of melanoma. Copyright © 2017 John Wiley & Sons, Ltd.  相似文献   

8.
The technology of the European Upper Palaeolithic yielded abundant evidence of the use of composite projectile heads, in the form of osseous points on the side of which one or several (micro)lithic elements are attached. Yet, little experimental work has been devoted to testing and assessing the parameters of use of this type of composite tips. In this paper we present a pilot experiment with replicas of Magdalenian composite spear tips, made of an antler point with one or two rows of flint backed bladelets. Two series of replicas were manufactured after the lithic and osseous record of, respectively, the Lower Magdalenian from southwest France (c. 20–18 Ky cal BP) and the Upper Magdalenian of Pincevent in the Paris Basin (c. 15–14 Ky cal BP). The 34 experimental composite heads were hafted to spears that were then shot with a spearthrower at the carcasses of two young deer. The results provide some insight into the performance characteristics of the osseous and lithic components, both in efficiency and durability. Finally, possible improvements of the experimental protocol are discussed, as well as the implications of our results for the understanding of projectile point variability in the Upper Palaeolithic.  相似文献   

9.
This paper applies spatial duration models to the analysis of cosponsorship coalitions in the U.S. House of Representatives. This approach provides a unique and simultaneous statistical analysis of ideological space (specifically, coalition formation) and geographical space. Typically, duration models are associated with temporal longitudinal data, but recently have been adapted to the spatial domain (Pellegrini and Reader 1996). In this paper, spatial duration models are further adapted to examine ideological space including a consideration of unobserved sources of spatial variation (or omitted variable bias). We examine two features of cosponsorship coalitions, breadth and clustering. Breadth is defined as the ideological distance between the two most extreme members of the coalition which is an important “signal” to the rest of Congress regarding the scope and broad appeal of the proposed legislation. In contrast, clustering refers to the distance between individual members of a coalition and reveals the tendency, or not, of ideologically similar members of Congress to support various bills. To examine breadth and clustering, we employ spatial duration models of cosponsorship that permit a multivariate analysis incorporating both the characteristics of members of Congress and the geographical regions they represent. Results indicate that cosponsorship coalition patterns are primarily determined by the content of the legislation, not the actions of the coalition leadership. While the leadership characteristics of sponsors have a limited effect on cosponsorship breadth, the size of the coalition is the primary determinent. Leadership characteristics also have little effect on cosponsorship clustering. Rather, clustering is due to members' policy preferences, as measured by distance to the coalition leader. In addition, the duration analysis results suggest that geographical proximity between members of Congress “overcomes” ideological distance. Finally, the spatial duration approach is noted as a fruitful methodology for examining explicitly spatial patterns in both ideological or geographical space.  相似文献   

10.
Hyena taphonomy is of great importance to studies of hominid evolution, since these carnivore taxa have the highest potential both to produce large osseous assemblages and to modify existing hominid-accumulated assemblages throughout the Old World. The three extant hyena species (brown: Parahyaena brunnea; striped: Hyaena hyaena; and spotted: Crocuta crocuta) are all significant bone collectors and modifiers. Spotted hyenas generally have the lowest potential to accumulate osseous remains, and the rate of accumulation varies based upon the type of den. The present research examines the remains accumulated by spotted hyenas in Masai Mara Cave, Masai Mara National Reserve, Kenya. The contents of this den were collected twice by the authors, with an 11-year span interceding. The taphonomic signatures of spotted hyena interaction with bone are presented, including species and skeletal element representation, breakage patterns, tooth marks, tooth puncture, edge polish, and gastric corrosion. Other taphonomic factors examined include rodent gnawing and weathering stage. The cave den assemblage was accumulated at a rate of 30.4 identified specimens and a minimum of 4.1 prey individuals per year. In addition, the osseous remains accumulated by spotted hyenas at multiple burrow dens within the Reserve were examined for taxonomic representation and multiple taphonomic parameters. Rates of accumulation at this type of den tend to be very low, due to differential usage by spotted hyenas and the more ephemeral nature of earthen dens.  相似文献   

11.
The Adani mine controversy is a significant new space of contestation in conflicts over coal mining and climate change in Australia. Proposed as one of the largest new coal mines in the world, the Adani (or “Carmichael”) mine has become a flashpoint between two broad coalitions—the pro‐mine coalition, consisting of governments, elements of the media, and mining interests, and the anti‐mine coalition, consisting of community groups, environmental non‐government organisations, activists, Indigenous communities, and farmers. Based on thematic analysis of news media articles and interviews with environmental actors in the Adani mine controversy, this article demonstrates how each coalition employs discursive scale frames and counter‐scale frames to represent and contest the controversy. We find that the pro‐mine coalition remains situated within a topographical spatiality, with a backwards oriented temporality, that obscures emergent topologies from their view. In contrast, while retaining capacity for operating within traditional scalar topographies, the anti‐mine coalition is more adept at negotiating topologies that increasingly define our social worlds. It is oriented towards a deep future horizon in which the Adani mine controversy represents an opportunity to reshape existing social and political orders. The sorts of scalar tactics documented here are likely at work in other resource extraction controversies, highlighting the need to attend to how scale may be being used to obscure irrationalities and injustices in extraction projects, and the potential for counter‐scale frames to help destabilise fossil fuel regimes.  相似文献   

12.
Occipitalisation of the atlas is one of the most frequent osseous anomalies of the atlas. It is characterised by the adhesion of the first cervical vertebra with the basilar part of the occipital bone. The most probable cause of the occipitalisation is a congenital disorder. The atlanto‐occipital fusion may lead to narrowing of the space for medulla oblongata, spinal cord and vertebral artery. This in turn may lead to many physiological symptoms. The skull from Twardogóra, Southern Poland, showed partial atlanto‐occipital fusion and presented an asymmetry in structure and shape of apertures for the vessels and nerves around the foramen magnum. Copyright © 2011 John Wiley & Sons, Ltd.  相似文献   

13.
14.
This article considers the fall of New Zealand's first coalition government under the Mixed Member Proportional (MMP) electoral system, through the prism of a ‘unified’ model of Cabinet durability. This model incorporates both the ‘structural attributes’ of the government at the time of its formation, as well as the stochastic ‘critical events’ that occur over its lifetime. However, the conventional attributes of the National–New Zealand First coalition were considered favourable, and the critical event that precipitated its demise did not by itself appear to be a sufficient condition for termination. It is argued that the hitherto unspecified structural attribute of intra‐party stability was a significant factor for this particular coalition, and that this case also demonstrates the cumulative impact of non‐terminal events in undermining the incentives for continued cooperation between coalition partners.  相似文献   

15.
Stephen Skowronek’s idea of political time is tested by applying it to Canada. Skowronek identified a recurring cycle in US presidential politics, in which a coalition was forged around a distinctive set of ideas, dominated the political scene, and then crumbled, making way for a new coalition; a president’s ability to act as an agent of change depended on his place in this cycle. The concept of political time offers insights for the study of Westminster democracies, but Skowronek’s typology cannot be transplanted from the US to the Canadian context. A political orthodoxy cannot be easily identified in Canada, and prime ministers cannot be clearly labeled as affiliated with or opposed to the ideas of a given era. Some seem determined to play a corrective role, accepting much of the orthodoxy but reconstructing some elements of it. This problem of classification is amplified by the very short term of some prime ministers, by the very long term of others, and by a multiparty system, which has meant that Canadians often end up with prime ministers who are out of synch with the dominant ideas of their age. When applying Skowronek’s ideas to Canada, they emerge as overly structural and not sensitive enough to the possibility that leaders can fail to perform according to type.  相似文献   

16.
A theoretical problem remains in the urban regime literature in that the connection between fiscal strain and regime fragmentation and thus the potential for coalition breakdown is not fully elaborated. Whelan et al. (1994) demonstrate that a shifting electoral coalition, in particular the emergence of a black majority electorate, can also lead to regime instability and fragmentation and the subsequent political struggles for dominance in an emerging governing coalition. In this paper a second mechanism for regime change is suggested; that is, that under conditions of economic restructuring and the subsequent fiscal strain, non-local actors, in this case national political actors operating primarily through party connections, can manipulate local political dependencies to forge governing coalition fragmentation and a regime change in a particular direction. This first finding is important because it highlights the often neglected role of party politics in the governing coalition/urban regime and the local state literature. Secondly, the complexity of state relations uncovered here does not bode well for a theoretically coherent concept of the local state but does display how the historical development of local social relations interacts with the state apparatus at the state and national level to create a particular ‘local’ politics. Finally, this transformation requires a shift in the location of political consensus building from the local democratic political electoral arena to a non-democratic quasi-public arena: a corporate-led governing coalition.  相似文献   

17.
The identification of projectile impact traces on archaeological faunal remains is an important issue for understanding prehistoric hunting behavior, especially in the Paleolithic and Mesolithic. From the beginning of the Upper Paleolithic in Europe, and earlier in Africa, projectiles tipped with osseous points were of great importance for subsistence; but thus far, no specific experimental reference has been developed to help identify the traces left by these points. In 2003 and 2004 two series of projectile experiments with antler points of Magdalenian design were organized, involving two ox calves and two female fallow deer as targets for bow and spearthrower shooting. The subsequent study demonstrates that positive identifications of impact traces left by osseous points can be made. The observation of 127 impact traces allowed us to distinguish three main types of traces: notches, punctures and perforations. The relationships between the nature of the impact traces and the (i) target species, (ii) characteristics of the impacted bones, and (iii) type of weapon are presented. Synthesized results are then discussed within the context of the European Upper Paleolithic and Mesolithic.  相似文献   

18.
This study presents a differential diagnosis of benign mandibular tumours identified in two adult burials from the precontact Maya city of Tikal, Guatemala. Both individuals were recovered from domestic structures that date to the Late Classic Period (AD 550–850). The osseous growths were interpreted as probable benign tumours based on evidence of localised growth, a circumscribed border, a dense texture and a lack of osteolytic activity or spiculate bone formation. Burial PTP‐026A is a middle adult (35–50 years) of indeterminate sex with evidence of a small dense, circular mass extending laterally from the right mandibular corpus. Macroscopic and radiographic assessment of this lesion provided a diagnosis of osteoma, a true neoplasm, or alternately, hyperplasia (e.g. exostosis) or hamartoma, which are not true neoplasms. Burial PTP‐017 is a probable young adult female (20–35 years) with a large osteoblastic lesion on the right anterior mandibular corpus. This dense, bony mass extends from the anterior margin of the mental canal, and shows a distinct boundary from the adjacent trabecular and cortical bone. The growth of the osseous mass displaced the right first premolar anteriorly. Radiographic assessment showed the presence of dense, radiopaque material, indicating significant calcification. This suggested a likely fibro‐osseous origin for this lesion, with a probable diagnosis of ossifying fibroma, or possibly osseous dysplasia. Although not definitive, our differential diagnosis was able to exclude a number of neoplastic and non‐neoplastic conditions that affect the jaws. This study provides the first reported cases of possible benign mandibular tumours in the ancient Maya. Copyright © 2009 John Wiley & Sons, Ltd.  相似文献   

19.
20.
Bipedal human motion is related to the original shape of the foot. Distortion and degenerative changes may be caused by failure in the complex chain of movements. There are few references to valgus flatfoot in either the palaeopathological or medical literature. The study of three French medieval series (Macon, Larina and Cutry) in the osteological collections of the CEPAM (UMR 6130 – CNRS/UNSA) at Valbonne (France) enabled us to define several significant osseous signs which provide evidence of abnormal biomechanical constraints following structural change in the foot. The consequences of the change of axis of the talar pulley, abnormal osseous contacts, and evolutionary modifications noticed in some synostoses of the tarsus, are particularly useful for study. Analysis of the location of arthritic change in the joint may produce an additional coherent argument to the diagnosis. The recognition of flatfootedness in an archaeological context provides a marker of health and of distress, which is all the more interesting since bones required for this diagnosis are often present and relatively well preserved in the excavations of burials. Copyright © 2006 John Wiley & Sons, Ltd.  相似文献   

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