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This paper focuses on the spatial distribution of bone tool production waste from two Mesolithic sites in Sweden, Ringsjöholm and Strandvägen, with well-preserved faunal remains including bone and antler artifacts. Local production on both sites has generated a variety of identifiable waste products deriving from complete chains of production, including unmodified bones, debitage and finished products. Identified categories include: blanks, removed epiphyses, bone flakes, and preforms. Identification of species shows that antler and bone from red deer were the preferred raw materials. Spatial statistical analyses confirm that different stages of bone tool production were organized within separate areas of the sites and that larger items were discarded in the water along the shorelines. Interestingly, blanks and preforms seem to have been stored under water for future use and demarcated clusters of bone flakes in association with dwellings represent “bone knapping floors” where production was more intense than in other areas.  相似文献   
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In this article, we utilize 25 years of data on the Milwaukee voucher program to test the relationships among organizational liabilities of newness, institutional affiliation, market‐share, and regulatory environment on the cumulative risk of school failure. Overall, we find that 41 percent of all private voucher schools operating in Milwaukee between 1991 and 2015 failed. Start‐up voucher schools, and those unaffiliated with a larger institution, have comparatively higher failure risk over time. The results of our analysis shed light onto one of the long‐term impacts of a public policy reform premised on social entrepreneurship. We conclude that policymakers should consider the consequences of organizational failure when utilizing nongovernment entities in the provision of public goods, and that scholars focus increased attention to understanding the negative externalities created by public entrepreneurship.  相似文献   
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Environmental change has a human dimension, and has had so for at least the last 10 000 years. The prehistoric impact of people on the Arctic landscape has occasionally left visible traces, such as house and field structures. More often than not, however, the only evidence available is at the microscopic or geochemical level, such as fossil insect and seed assemblages or changes in the physical and chemical properties of soils and sediments. These records are the subject of SEAD, a multidisciplinary database and software project currently underway at Umeå University, Sweden, which aims to create an online database and set of tools for investigating these traces, as part of an international research infrastructure for palaeoecology and environmental archaeology.  相似文献   
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Tumlehed is the most well‐preserved and complex prehistoric rock painting in the coastal region of south‐west Sweden. Originally reported and described in 1974, we re‐documented the panel using digital and IR photography, DStretch image enhancement software, and non‐destructive PXRF spectroscopy. This re‐documentation revealed a more complex image inventory with several previously unknown motifs and image details. The new data provide a better basis for identifying motif categories, the organization of the panel, the chronological sequence, and different frequentation periods. We report on the only known boats with an elk‐head stem in southern and western Scandinavian rock art, the emergence of rock art boat depictions in the region, and evidence for long‐distance maritime journeys and sea‐mammal hunting in the later Stone Age. Comparisons to similar images with shoreline data in Fennoscandia narrow the time range for the date of the painting to 4200–2500 BC.  相似文献   
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