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Mapungubwe (AD 1220–1290) is generally regarded as the first urban centre in southern Africa, functioning as the seat of power for an extensive but short-lived polity. More than 80 years of excavations here, and at its nearby predecessor K2 (c. AD 1000–1220), resulted in a substantial assemblage of material remains from elite and commoner contexts. This assemblage includes a large collection of worked bone objects, such as needles, awls, tubes and objects of personal adornment. Of particular interest are the bone arrowheads and link-shafts, of which a significant number of specimens were found complete and intact. Such quantities of well-preserved worked bone objects are unique in the archaeological record of the region. The worked bone assemblages from these two sites provide a rare opportunity to study multiple components of the production process as well as the use context of bone objects. In this paper, we characterise the K2 and Mapungubwe worked bone industries through various morphological, technological, use-trace and contextual approaches and discuss the significance of these aspects in terms of raw material selection and manufacture and archaeological use context. In particular, this study shows the complexity of these worked bone industries over time.  相似文献   
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This paper examines how a group of Hong Kong working mothers use the internet in performing and realizing their paid work and domestic role identities. The internet is a technology-enabled space and also what Michel de Certeau calls a ‘practiced place’, where its nature and functions are necessarily determined by the actions and practices of agents. Through participant observation and the analysis of a sample of chatroom and forum messages from a user-driven Hong Kong-based parenting website called Happy Land, I examine the relationship between this virtual space and its users. I find that the website has developed beyond its technology-mediated nature into a community of face-to-face friendships and social and emotional support. In effect, this virtual space plays a role in the social reproduction of the contemporary dual-earner family by enabling working mothers who use the website to perform roles in production and reproduction respectively.  相似文献   
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In the constellation of the eighteenth-century revolutions, the French events have always occupied a dominant position. Consequently the other European upheavals have been considered as being provoked or strongly influenced by France. Yet, the Dutch revolutions in the 1780s and 1790s provide some important nuances to this interpretation. Before the French took over the Bastille, there was already a Dutch revolution with devoted Patriots, speaking about rights of man and constitutions. The Patriots had to flee abroad in 1787. In 1795, thanks to the French Army, they were able to return to their drawing boards, eager to think anew their government and society. This paper investigates how they did it and whether the American and French precedents were so influential after all in the construction of the Batavian Republic.  相似文献   
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Marsola, J.C.A., Grellet-Tinner, G., Montefeltro, F.C., Sayão, J.M., Hsiou, A.S. & Langer, M.C., 2014. The first fossil avian egg from Brazil. Alcheringa 38, 563–567. ISSN 0311-5518.

In contrast to the rich record of eggs from non-avian dinosaurs, complete eggs attributable to Mesozoic birds are relatively scarce. Nevertheless, several well-preserved specimens have been discovered over the last three decades revealing functional and phylogenetic characters that shed light on the breeding strategies of extinct birds. Here we report the first fossil avian egg from Brazil, which was discovered in Upper Cretaceous strata of São Paulo in the southeastern part of the country. The taxonomic identity and structural features of the biomineralized tissues were determined using a combination of Scanning Electron Microscopy, Wave Dispersion Energy analyses and Computed Tomography. These show that the 125.5-μm-thick shell of the 31.4?×?19.5?mm egg incorporates three structural layers of similar thickness with both prismatic and aprismatic boundaries. Close similarity between the Brazilian bird egg and those of enantiornithines from the Upper Cretaceous Bajo de la Carpa Formation (Río Colorado Subgroup) of Argentina advocates affinity with basal Ornithothoraces. Furthermore, coherency of their depositional contexts might imply a compatible preference for breeding and nesting environments.

Júlio Cesar de A. Marsola [], Annie Schmaltz Hsiou [] and Max C. Langer [], Laboratório de Paleontologia de Ribeirão Preto, Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, Universidade de São Paulo, Avenida Bandeirantes 3900, Ribeirão Preto, São Paulo state, 14040-901, Brazil. Gerald Grellet-Tinner [], Centro Regional de Investigaciones La Rioja—Consejo Nacional de Investigaciones Científicas y Técnicas, Entre Ríos y Mendoza s/n, 5301 Anillaco, Argentina; Orcas Island Museum, PO Box 134, 181 North Beach Road, Eastsound, WA 98245. Felipe C. Montefeltro [], Departamento de Zoologia, Universidade Estadual Paulista, Avenida 24A 1515, Rio Claro, São Paulo State, 13506-900, Brazil. Juliana M. Sayão [], Laboratório de Diversidade do Nordeste, Núcleo de Biologia, Centro Acadêmico de Vitória, Universidade Federal de Pernambuco, Rua do Alto do Reservatório s/n, Bela Vista, Vitória de Santo Antão, Pernambuco state, 52050-480, Brazil. Received 18.12.2013; revised 30.4.2014; accepted 18.5.2014.  相似文献   
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