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The need for experiments to study physical aspects of craft of the past is stated, as well as the necessity for them to have clear aims and to follow the established principles of scientific enquiry. These principles are discussed in this joint paper by ten maritime archaeologists and others, together with methods and some points of management critical to their application in this field.  相似文献   
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We review evidence from human biology—paleopathological and isotopic paleodietary studies on ancient Maya skeletons—to assess the validity of ecological models of the Classic Maya collapse, in which elevated disease and deteriorating diet are commonly assumed. To be upheld, the health arguments of ecological models require that the Maya disease burden (1) was greater than that for many other societies and (2) increased over the span of occupation. The dietary argument requires (1) consistent change in diet from Preclassic and Early Classic Periods to the Terminal Classic and (2) increasing social divergence in diet. A correlation between diet and disease is necessary to link these arguments. Neither pathology nor isotopic data consistently support these criteria. Instead, it appears that local environmental and political factors created diversity in both disease burden and diet. In view of the human biological data, we are skeptical of ecological models as generalized explanations for the abandonment of Classic Maya sites in the southern lowlands.  相似文献   
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Madagascar's culture is a unique fusion of elements drawn from the western, northern, and eastern shores of the Indian Ocean, and its past has fascinated many scholars, yet systematic archaeological research is relatively recent on the island. The oldest traces of visitors are from the first century AD. Coastal settlements, with clear evidence of ties to the western Indian Ocean trading network, were established in several places over the next millennium. Important environmental changes of both plant and animal communities are documented over this period, including the extinctions of almost all large animal species. Urban life in Madagascar began with the establishment of the entrepôt of Mahilaka on the northwest coast of the island in the twelfth century. At about the same time, communities with ties to the trade network were established around the island's coasts. From the fourteenth to the sixteenth century, social hierarchies developed in several regions of the island. During the succeeding two centuries, Madagascar saw the development of state polities.  相似文献   
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Policy advocacy is an increasingly important function for many nonprofit organizations, yet their advocacy activities have largely escaped theoretical grounding. The literature on nonprofits has described how they engage in policy advocacy, without linking them to theories of policy change. The policy studies literature, on the other hand, has explained how various forms of influence result in policy change, but has largely ignored organizational perspectives on those processes. These two literatures remain largely disconnected. Drawing upon interviews with a purposive sample of policy advocacy directors at 31 nonprofit organizations, this study applies Q‐methodology to identify and describe six distinct policy advocacy strategies employed by the organizations, and their resonant theoretical views of policy processes. These findings suggest strategic approaches for nonprofits seeking to influence policy processes. They also enhance the academic literature on policy processes by adding the advocates’ views and expectations. Implications for further research are also identified.  相似文献   
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Plusquellec, Y. &; Wright, A.J., October 2017. Revision of the Early Devonian tabulate coral Pleurodictyum bifidum from New South Wales. Alcheringa 41, xxx–xxx. ISSN 0311-5518.

The tabulate coral Pleurodictyum bifidum Jones, 1944 Jones, O.A., 1944. Tabulata and Heliolitida from the Wellington district, N.S.W. Journal and Proceedings of the Royal Society of New South Wales 77, 3339. [Google Scholar], from the Early Devonian (Pragian or lower Emsian) Garra Formation of central New South Wales, Australia is revised on the basis of the holotype and three other specimens. It is selected as the type species of the new monotypic genus Bifidomeria (Family Roemeriidae), which differs from Roemeria in its strictly cerioid corallum, its bifid septal spines and aspects of its microstructure. Study of the detailed microstructure of two other tabulate corals from the Devonian of New South Wales has led to the following revised generic assignments: Michelinia progenitor Chapman, 1921 Chapman, F., 1921. New or little known fossils in the National Museum. Part XXV—some Silurian tabulate corals. Proceedings of the Royal Society of Victoria 33, 212225. [Google Scholar], previously assigned to Roemeripora, is assigned to Roemeria, and Holacanthopora clarkei Wright &; Flory, 1980 Wright, A.J. &; Flory, R.A., 1980. A new Early Devonian tabulate coral from the Mount Frome Limestone, near Mudgee, New South Wales. Proceedings of the Linnean Society of New South Wales 104, 211219. [Google Scholar] is assigned to Michelinia.

Yves Plusquellec [], Université de Bretagne Occidentale, CNRS-UMR 6538 ‘Domaines océaniques’, Laboratoire de Paléontologie, UFR Sciences et Techniques, 6 avenue Le Gorgeu, CS 98837, F-29283 Brest, France; Anthony Wright [], GeoQuEST Research Centre, School of Earth &; Environmental Sciences, University of Wollongong, Wollongong NSW 2522, Australia.  相似文献   
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