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Benson, R.B.J., Fitzgerald, E.M.G., Rich, T.H. & Vickers-Rich, P., 2013. Large freshwater plesiosaurian from the Cretaceous (Aptian) of Australia. Alcheringa 37, 1–6. ISSN 0311-5518

We report a large plesiosaurian tooth from the freshwater early–middle Aptian (Early Cretaceous) Eumeralla Formation of Victoria, Australia. This, combined with records of smaller plesiosaurian teeth with an alternative morphology, provides evidence for a multitaxic freshwater plesiosaurian assemblage. Dental and body size differences suggest ecological partitioning of sympatric freshwater plesiosaurians analogous to that in modern freshwater odontocete cetaceans. The evolutionarily plastic body plan of Plesiosauria may have facilitated niche differentiation and helped them to exclude ichthyosaurs from freshwater environments during the Mesozoic. However, confirmation of this hypothesis requires the discovery of more complete remains.

Roger B.J. Benson [roger.benson@earth.ox.ac.uk], Department of Earth Sciences, University of Oxford, South Parks Road, Oxford OX1 3AN, UK; Erich M.G. Fitzgerald [efitzgerald@museum.vic.gov.au], Thomas H. Rich [trich@museum.vic.gov.au], Museum Victoria, GPO Box 666, Melbourne, Victoria 3001, Australia; Thomas H. Rich and Patricia Vickers-Rich [pat.rich@monash.edu], School of Geosciences, Monash University, Clayton, Victoria 3800, Australia. Received 30.10.2012; revised 27.1.2013; accepted 31.1.2013.  相似文献   
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This article examines how younger migrant women from Turkey maneuver the public and private spaces of their everyday lives in a neighborhood in Germany, and how they challenge and affirm the patriarchal practices and gender norms that husbands, fathers, and older migrant women seek to impose within and outside private homes. Younger migrant women selectively comply with gendered and generational norms of veiling and dress, while at the same time also reworking gender roles, and avoiding and transgressing masculinist spaces. Younger migrant women's practices and spatial representations in mental maps reveal the complex entanglements of compliances and resistance, and dispel simple assumptions of being overwhelmingly victimized by their potentially violent men that are so prominent in contemporary Western societies.  相似文献   
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Though Otto von Bismarck exercised great power as Chancellor of the German Empire, historians have overlooked the extent to which it was threatened during the 1880s by the imminent accession of Crown Prince Frederick William. The article focuses on the means by which Bismarck strove to maintain his power, and how many of his plans were thwarted by the crown prince. The heir to the throne had to also fend off his wife's campaign to enact radical liberal reforms during her husband's coming reign. The ability of the crown prince to resist the campaigns of both his wife and Bismarck shows that his influence was indeed considerable, and that estimates of Bismarck's power are in need of revision.  相似文献   
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We investigate the temporal and environmental relationships between the terraced hill slopes of Politiko-Koloiokremmos and the adjacent Bronze Age settlement of Politiko-Troullia in foothills of the Troodos Mountains, central Cyprus. Mapping of 102 stone walls on Koloiokremmos is compared with 66 walls farther afield on Cyprus to create a six-part terrace typology. Sherd counts from 174 2-m radius collection circles over approximately 20 ha on Troullia and Koloiokremmos were used to create interpolated sherd density surfaces revealing distinctly different patterns of land use for four major archaeological eras between the Cypriot Bronze Age and Medieval Period. We compared sherd density patterns according to terrace types, length, slope and vegetation cover determined by SAVI (Soil-Adjusted Vegetation Index) from Ikonos and Quickbird satellite imagery.The most robust sherd patterning indicates Prehistoric Bronze Age settlement at Troullia, as confirmed by soil resistivity and excavation, and multi-period land use on Koloiokremmos immediately upslope of the village that may be associated with agricultural terracing. Scattered sherd concentrations indicate later use of this landscape as an agricultural hinterland for the Iron Age city of Tamassos. Sherds and a down slope spread of roof tiles from the Roman through Medieval periods suggest an isolated structure near the crest of Koloiokremmos. Longer terraces correlate with greater vegetation cover and are interpreted as agricultural, while shorter terraces, apparently for erosion control and arboriculture, are significantly related to Prehistoric Bronze Age sherd patterns. Our results suggest that coordinated analysis of archaeological, geographical and remotely sensed environmental data associated with terraced landscapes can be used to infer long-term patterns of agricultural land use.  相似文献   
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The differences between Middle and Upper Palaeolithic cultures from Europe have been likened to the contrast between generalized and complex hunter–gatherers. A test of this model is undertaken by comparing the types, amount, severity and timing of episodes of enamel hypoplasia between the two periods among specimens from western Europe and the circum-Mediterranean area. The earlier sample consists of 59 dentally immature individuals with 128 primary and 154 permanent teeth while the later sample consists of 47 dentally immature individuals with 162 primary and 125 permanent teeth. It was predicted that the Upper Palaeolithic would show more variation in the attributes noted above as a consequence of increased social differentiation. While the prevalence (50% of individuals) and severity of enamel hypoplasia do not differ between the samples, the Upper Palaeolithic component is significantly more variable in the types and timing of enamel defects. Localized hypoplasia of the primary canine is absent from the Middle Palaeolithic but very common among Upper Palaeolithic children. Earlier work has linked this enamel defect to craniofacial osteopenia due to low bioavailability of vitamin A. Linear enamel hypoplasia peaks at age 3·5 years in the Middle Palaeolithic sample but is as common at age 2·0 as 5·0 years in the Upper Palaeolithic sample. The age distribution differs significantly. Peak age at stress, combining all types of enamel hypoplasia, is 3·5 years in the Middle Palaeolithic and 0·5 years in the Upper Palaeolithic. The major contrast between the Middle and Upper Palaeolithic in terms of enamel hypoplasia is the advent of stressful episodes in early infancy in the Upper Palaeolithic. This is attributed to the low bioavailability of vitamin A due to the synergistic effects of malnutrition and infection exacerbated by a net increase in population density among socially competitive family lineages.  相似文献   
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We argue here that processes of political centralization and hierarchy building can be profitably explored by focusing on how resources were strategically manipulated in search of power by people organized in social networks of varying sizes and spatial extents. Adopting this perspective encourages reconsideration of the ways in which such core concepts as structure, agency, and society can be redefined to cast new light on ancient power contests. In addition, we suggest that a network approach complements traditional emphases on processes of domination and resistance by drawing attention to the importance of alliances in shaping political formations. The potential utility of these precepts is illustrated in an example drawn from our research on Terminal Classic (800–1000 AD) political struggles in the Naco valley of northwestern Honduras. Special attention in this case centers on the manner in which craft products were manipulated by people of varying ranks to define and achieve goals as well as to control the actions of others. The study’s broader implications for the analysis of ancient political relations are highlighted at the essay’s conclusion.  相似文献   
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ABSTRACT This paper uses a stochastic frontier production-function model to measure and compare productivity efficiency in the manufacturing sector of states in the United States over the period 1959–1972. Based on this model we find considerable variations in productive efficiency across states. A large portion of the variation is found to be related to regional differences in labor-force characteristics, levels of urbanization and industrial structure. We also examine the relationship between productive efficiency and the subsequent growth of manufacturing and find some evidence of a weak relationship between efficiency and the growth of employment.  相似文献   
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