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991.
992.
N. Mercier H. Valladas L. Froget J.-L. Joron J.-L. Reyss S. Weiner P. Goldberg L. Meignen O. Bar-Yosef A. Belfer-Cohen M. Chech S.L. Kuhn M.C. Stiner A.-M. Tillier B. Arensburg B. Vandermeersch 《Journal of archaeological science》2007
The thermoluminescence dating method was applied to 77 heated flints from the Mousterian layers of Hayonim Cave in order to provide a precise TL-based chronology for this important Levantine sequence. A detailed dosimetric study was performed by using 76 dosimeter capsules and revealed strong spatial dose-rate variations. In parallel, Fourier transform infrared spectrometry enabled the identification of various mineral assemblages in the sediments of the cave and to localize the boundaries of these assemblages. By comparing these two data sets, it is shown that low dose-rate values (∼500 μGy/a) are systematically recorded in areas where the calcite-dahllite (CD) assemblage is preserved, whereas higher values (up to 1300 μGy/a) are associated with the leucophosphite, montgomeryite, variscite and siliceous aggregates (LMVS) assemblage. The dosimetric and mineralogical information was combined in order to assess, where possible, the dose-rate experienced by each flint during its burial. Some of the flint samples analyzed were too close to mineral assemblage boundaries and were therefore discarded. This rigorous selection led to TL ages ranging from 230 to 140 ka for the lower part of the Mousterian sequence (layers F and Lower E), which contains lithic industries characterized by blade production using the laminar method. 相似文献
993.
John H. Blitz 《Journal of Archaeological Research》2010,18(1):1-39
In recent years the pace of research on the late prehistoric Mississippian societies of eastern North America has accelerated. New data, methods, and theoretical goals are changing perspectives in Mississippian archaeology. Regional overviews and site syntheses provide unprecedented insights into the Mississippian phenomenon at local, regional, and continental scales. Traditional culture history, processualism, historical processualism, iconography, and neo-Darwinian archaeology are active theoretical orientations. Important research focuses on variability in Mississippian sociopolitical formations over time, organizational diversity among contemporaneous societies, and sources of political power. The new historicism and iconography place agency, identity, origins, factionalism, ideology, and meaning at the center of culture change, while many processualists continue to focus on developmental histories, economy, and control of material resources. Advances in physical and chemical analyses and the availability of remote sensing techniques are changing how Mississippian archaeology is conducted and expanding the kinds of data that are recovered. These diverse interests, methods, and goals have created considerable eclecticism in Mississippian archaeology. 相似文献
994.
MYRON H. BRIGHT 《Journal of Supreme Court History》2010,35(1):25-34
In May 2009, a decision of the United States Supreme Court with North Dakota roots turned fifty years old. A case unique in the annals of the law, Dick v. New York Life Insurance Company 1 still fascinates lawyers today. Factually, the case presented a strange question: could an experienced hunter accidentally shoot himself not once, but twice? Some of North Dakota's finest lawyers, including Philip Vogel, Donald Holand, and Norman Tenneson, aimed to get to the bottom of that matter. The judges were equally impressive: Judge Ronald Davies of the federal district court; Judge John Sanborn of the U.S. Court of Appeals for the Eighth Circuit; and Chief Justice Earl Warren and Justice Felix Frankfurter. Finally, as a matter of Supreme Court jurisprudence, Dick may have been the last time the High Court granted a petition for certiorari in a case that turned almost exclusively on questions of fact. In honor of its golden anniversary, this article recounts the captivating story of Dick v. New York Life. 相似文献
995.
In one of the first quantitative designs, we explore the impact of both legalisation and flexibility on regime effectiveness, using data on international environmental institutions. One of the main implications is that ‘precision’ is an important determinant of regime performance. If the rule and norm system is well defined, well understood and clear, then a regime tends to be more effective in addressing an environmental problem. We do not find evidence, however, that ‘hard law’ is more effective than ‘soft law’ or that delegation mechanisms may be relevant. Second, flexibility in the regime structure increases regime performance – regular instead of subsidiary bodies enhance flexibility and thus have a positive effect on a regime's environmental problem management. Flexibility in states' agenda setting power, membership and decision making do not seem to have a crucial influence, though. 相似文献
996.
The adsorption onto other minerals of charged gold nanoparticles, carried by gas ascending from the Earth’s interior, is an important component of their transport and deposition in surficial cover such as alluvial, aeolian, and glacial sediments. To simulate the adsorption of these particles, an experiment was conducted in which a flow of air that contained gold nanoparticles was passed upward through a sample of alluvium from the middle–lower reaches of the Yangtze River. These experiments showed that gold nanoparticles are adsorbed on kaolinite, halloysite, goethite, and hematite in the alluvial cover. Both the gold nanoparticles and minerals (i.e., kaolinite, halloysite, goethite, and hematite) carry surface charges that provide them with excellent adsorption properties. This study showed that the specific mineral composition of surficial alluvial cover affects the concentration of gold nanoparticles in the ascending gas. This phenomenon may plausibly be used in exploration for concealed gold, copper–gold, and silver–gold deposits in areas of thick alluvial cover. Geofluids (2010) 10 , 438–446 相似文献
997.
998.
This paper presents a pilot study designed to test the use of oxygen isotopes for investigating aspects of early herding practices in the Neolithic of western Asia, using the site of Çatalhöyük in central Anatolia as a case study. Time‐sequenced δ18O values in dental enamel of archaeological sheep are assessed for post‐depositional diagenetic effects and compared with seasonal δ18O meteoric water values in the region today. The evidence is used to indicate the environmental conditions in which individual sheep spent their first year, enabling management of breeding and birthing seasons, and movement to seasonal pastures, to be investigated. 相似文献
999.
Friendships Moderate an Association Between a Dopamine Gene Variant and Political Ideology 总被引:1,自引:0,他引:1
Scholars in many fields have long noted the importance of social context in the development of political ideology. Recent work suggests that political ideology also has a heritable component, but no specific gene variant or combination of variants associated with political ideology have so far been identified. Here, we hypothesize that individuals with a genetic predisposition toward seeking out new experiences will tend to be more liberal, but only if they are embedded in a social context that provides them with multiple points of view. Using data from the National Longitudinal Study of Adolescent Health, we test this hypothesis by investigating an association between self-reported political ideology and the 7R variant of the dopamine receptor D4 gene (DRD4), which has previously been associated with novelty seeking. Among those with DRD4-7R, we find that the number of friendships a person has in adolescence is significantly associated with liberal political ideology. Among those without the gene variant, there is no association. This is the first study to elaborate a specific gene-environment interaction that contributes to ideological self-identification, and it highlights the importance of incorporating both nature and nurture into the study of political preferences. 相似文献
1000.