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991.
ABSTRACT State per capita income differences narrowed considerably between 1939 and 1976. However, this convergence has been incomplete. We examined the sources of relative per capita income growth using an augmented growth model and a panel of the 48 contiguous states from 1939 to 2004. We explored the effect of tax burdens, public infrastructure, size of private financial markets, rates of business failure, industry structure, climate, educational attainment, and technology production. Our results show that a state's technology and its college attainment rates are the main factors that allow some state's per capita income to remain above those of other states.  相似文献   
992.
Cultural landscapes were prominent during the Early Roman period when agronomic knowledge allowed the spread of intensive land exploitation in most of the available land. The aim of this contribution is to explore whether for the Campania region (Southern Italy) archaeoenvironmental data would support continuity or change in the cultural landscape of Roman tradition in the 4th and 5th centuries. To do so, new data from two sites located on the northern slopes of the Vesuvius, both buried by the AD 472 eruption have been investigated. Charcoal analysis, 14C dating, and chemical analysis of organic residues were carried out in order to study the landscape and the food production at these sites. The results suggest the persistence of the Roman cultural landscape until the 4th and 5th centuries in this area. The landscape is in fact strongly marked both in agriculture and woodland exploitation and management, being characterized by managed chestnut forests as well as valuable cultivations of walnut, large vineyards, olive groves, and probably orchards and crops. The integrated approach with archaeobotanical and archaeometric analyses proves to be a powerful method for the study of the past landscapes, providing a good insight into the environment. Furthermore, this study provided the most ancient evidence of chestnut silviculture for wood.  相似文献   
993.
This study addresses buff-firing clay sources in dynamic alluvial settings along Arizona’s Gila River in the U.S. Southwest. We establish clay resource distribution relative to the geomorphic histories of the Lower and Middle Gila River based on 38 clay samples and ethnographic data from two US Bureau of Reclamation (BOR) projects. Buff-firing clayey alluvium, deposited in the Gila River floodplain 800 to 1,500 or more years ago, was a surficial ceramic raw material source for prehistoric Hohokam and lowland Patayan potters. This geomorphic unit was later removed in some places and buried by up to 3-4 m of sediment in others, reducing the availability of buff-firing clays in the Hohokam Classic period and requiring historic Pee Posh and Akimel O’odham potters to dig pits to access it. Sources were further destroyed in catastrophic floods in the late 19th and early 20th century, affecting ceramic manufacture patterns and ultimately contributing to the decline of pottery production by the O’odham living in the Gila River Valley. Our results contribute to regional ceramic ecology and should also be of interest to others investigating alluvial clay use in general or buff-firing alluvial clays in particular. The study also illustrates the value of combining geomorphic and ethnographic data to examine major changes in resource distribution and use.  相似文献   
994.
Twenty‐six tesserae (red, orange, yellow, light amber, green, blue and white) from the balneum of the villa at Faragola (Ascoli Satriano, Foggia) have been examined by colorimetry, ICP–MS, ICP–OES and SEM–EDS. Different types of calcareous sands have been used as the source of silica (network former), also providing the stabilizing agent. A natron‐type soda source served as the network modifier; however, the use of a sodium‐rich plant ash and the recycling process have been hypothesized for the production of two tesserae (FT 1 red and FT 3 orange). The colouring and opacifying agents were Cu oxide (cuprite, orange), metallic copper (red), Pb antimonates (yellow), Ca antimonates (white), a mixture of copper (Cu2+) and Pb antimonates (green), a mixture of cobalt (Co2+) or copper (Cu2+) and Ca antimonates (blue). The light amber tesserae should owe their colour to iron (Fe3+) alone or associated with sulphide (S2?) and Ca antimonates. It is likely that the Faragola tesserae were locally produced in a secondary glass workshop.  相似文献   
995.
Eighty‐one samples taken from 68 glass beads found in southwestern Poland on sites of the Lusatian culture from the Hallstatt C and Hallstatt D subphases were analysed by EPMA. A subsample of 18 of these were additionally subjected to analysis by means of LA–ICP–MS in order to validate the results obtained by EPMA. Some glass was made using mineral soda and some using plant ash rich in sodium. Both high‐magnesium soda–lime glass (HMG) and low‐magnesium soda–lime glass (LMG) were identified. A large number of samples are characterized by low MgO content and medium K2O content (LMMK glass), combined with low concentrations of CaO and high Fe2O3 and Al2O3. All the LMMK glass contains numerous silica crystals and inclusions composed of a number of elements (most frequently Cu, Co, Sb, As, Ag, Ni and Fe). The LMMK glass was presumably made in Europe during the Hallstatt C.  相似文献   
996.
Community‐based conservation is experiencing a crisis of identity and purpose as a result of a disappointing track record and unresolved deficiencies. The latter include over‐simplified assumptions and misconceptions of “community,” the imposition of externally designed and driven projects at the community level, a focus on conservation outcomes at the expense of community empowerment and social justice, and limited attention to participatory processes. New approaches are urgently needed to address these weaknesses and to counter a rising trend towards environmental protectionism and a preference for conservation approaches at an eco‐regional scale that threaten the interests of local and Indigenous communities. We propose that three core principles of community‐based participatory research (CBPR)—(1) community‐defined research agenda; (2) collaborative research process; and (3) meaningful research outcomes—hold much promise. Drawing on the experience of a research partnership involving the James Bay Cree community of Wemindji, northern Quebec, and academic researchers from four Canadian universities, we document the process of applying these principles to a community‐based conservation project that uses protected areas as a political strategy to redefine relations with governments in terms of a shared responsibility to care for land and sea. We suggest that basic assumptions of CBPR, including collaborative, equitable partnerships in all phases of the research, promotion of co‐learning and capacity building among all partners, emphasis on local relevance, and commitment to long‐term engagement, can provide the basis for a revamped phase of community‐based conservation that supports environmental protection while strengthening local institutions, building capacity, and contributing to cultural survival.  相似文献   
997.
E. FRAHM 《Archaeometry》2012,54(4):623-642
Despite predictions in the 1980s that electron microprobe analysis (EMPA) would become a popular technique for obsidian sourcing, few studies have used it with this goal, and most of them are now outdated and unrepresentative of modern EMPA. For example, Merrick and Brown (1984 ) recorded their data on punch cards. Furthermore, these studies destructively prepared artefacts for analysis. The research at hand endeavoured: (1) to establish the modern capabilities of EMPA for obsidian sourcing; and (2) to develop and evaluate procedures for non‐destructive artefact analysis. Issues such as diagenetic effects and compatibility with NAA and XRF data were also investigated.  相似文献   
998.
This paper describes two approaches to the facial approximation of three individuals from the Wairau Bar burial site (New Zealand). Two individuals were approximated working in direct reference to the remains and incorporated manual drafting. The third individual, ‘Aunty’ (the respectful title given by the iwi Rangitane elders) was approximated from CT scans and using computer graphics. The computer graphic approach enabled a greater level of precision in the application of the research and recommendations that inform a facial approximation, and facilitated collaboration with appropriate expertise. The computer-graphic approach, however, also resulted in a more photographic facial appearance, which can imply a greater level of knowledge about hard/soft tissue relationships than is currently available.  相似文献   
999.
South American archaeologists use the term landscape to analyze a broad range of relationships. Examples include intensive agriculture and political power, myth and place, and climate change and cultural development. Landscape archaeology is necessarily spatial analysis, but scholars work at different scales and use different methods. This essay highlights the influence of geography, anthropology, and new methodologies on four definitions of landscape: ecological habitat, built environment, a stage for performance, and integrating subsistence and settlement. In a number of cases, landscape archaeologists, stakeholders, and researchers from different traditions work at different scales to meaningfully share information, clarify their differences, and compare their analyses and conclusions.  相似文献   
1000.
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