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991.
One purpose of the Advocacy Coalition Framework (ACF) is to explain policy change. Previous holistic reviews of the ACF by Weible, Sabatier, and McQueen (2009) and Pierce, Peterson, Jones, Garrard, and Vu (2017) of the framework have not explicitly analyzed all the concepts and their interactions in a systematic manner. To address this gap and inform scholars and practitioners about past findings, strengths, weaknesses, and opportunities for future research, this article analyzes how the ACF's theory of policy change is applied to 148 policy processes among 67 journal articles from 2007 to 2014. Similar to Weible et al. (2009), this research finds the frequent use of multiple primary pathways to policy change, infrequent use of many of the ACF's concepts, a plurality of applications in the environment and energy domain, comparison of subsystems, and a need for greater clarity and transparency among applications. Unlike Weible et al. (2009), this article explores associations between primary pathways and policy domains, the frequency of associations between primary pathways and secondary components, policy change and stasis, and identifies threats to internal validity of key ACF concepts.  相似文献   
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Determination of the source of Spondylus objects is essential for the interpretation of Late Neolithic exchange systems and the social role of shell ornaments. We performed stable isotope analysis combined with cathodoluminescence microscopy study on ornaments (beads, bracelets) made of Spondylus shells excavated at the Aszód-Papi földek archaeological site in Hungary, to define their origin. For comparison Spondylus finds from Neolithic sites of Greece, modern Spondylus shells from the Aegean and the Adriatic, as well as fossil Spondylus and Ostrea shells from the Carpathian Basin were also examined. Oxygen isotope composition of Spondylus finds from Aszód ranges between ?1.9 and 2.1‰ and overlaps with the oxygen isotope range of shell objects from other Neolithic sites. Modern Spondylus shells from the Aegean and the Adriatic show overlapping δ18O values with one another and with the Neolithic objects; while recent shells of the Black Sea clearly are separate isotopically from the Mediterranean ones and most of archaeological artefacts. Spondylus shells from the Aszód site have Mediterranean origin; their source can be the Aegean or the Adriatic. Based on a former strontium isotope study the use of fossil Spondylus shells is excluded as raw material used for ornaments, however, in recent years the use of fossil shells was reintroduced. The shell ornaments from Aszód-Papi földek and the fossil oyster shells collected from the Carpathian Basin exhibit some overlapping oxygen isotope values; however, cathodoluminescence microscopy indicates that the Spondylus objects retained their original aragonite material. Diagenetic calcite, which occurs typically in the fossil shells, was not detected in the ornaments suggesting that the studied objects were made of recent shells. Calcitic parts observed in some Spondylus objects are not related to fossilisation.  相似文献   
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Summary. The earliest farming communities in Southern England were for a long time represented solely by the structural remains left behind in the form of burial monuments, henges and causewayed enclosures; only recently, through problem-oriented surface collection, has any attempt been made to locate their settlements. This paper suggests that such attempts have been limited by the very desire to locate 'sites' which made the technique attractive in the first place. Instead it is suggested that we should be attempting to 'think Mesolithic', and by using our knowledge of Neolithic settlement and land-use strategies, attempt to locate zones of continuity which undoubtedly occurred in certain 'favourable locations'within the landscape. Case studies from East and West Hampshire are discussed and two types of adaptive behaviour are identified.  相似文献   
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