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P. Schmidt  A. Morala 《Archaeometry》2018,60(5):885-897
The earliest evidence of flint and chert heat treatment was found in the ~21.5–17 ka old European Solutrean culture. The appearance of pyrotechnology as part of the production of stone tools has important implications for our understanding of Upper Palaeolithic technological evolution and the specific adaptations during the last glacial maximum in Europe. However, the techniques and procedures used to heat‐treat rocks during the Solutrean remain poorly understood. No direct archaeological evidence has so far been found and the most promising approach is to understand these techniques by determining the parameters with which flint and chert were heated at that time. In this study, we investigate the heating temperature of 44 heat‐treated laurel‐leaf points from Laugerie‐Haute, using a non‐destructive technique based on infrared spectroscopy. Our results document that most of the artefacts were heated to a narrow interval of temperatures between 250 °C and 300 °C. This indicates a standardized technique that allowed to created similar conditions during successive heating cycles. The implications of these results for our understanding of the technical complexity during the Solutrean must be discussed in the light of different heating techniques used at different places and periods.  相似文献   
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Vedic pāthas     
Ohne Zusammenfassung  相似文献   
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Fourteen glass objects recovered from excavations at the ancient city of Tall Zirā‛a, Jordan, were analysed using laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) to determine the period and origin of manufacture. The composition of glasses manufactured in the Late Bronze Age (LBA) and Iron Age are distinctly different, therefore major element analysis can be used to distinguish between the groups relatively easily. The LA-ICP-MS analysis provided quantitative trace element data which were used to determine the provenance of those glasses identified as LBA. This research discusses the implications of the presence of both Egyptian and Mesopotamian LBA glasses and examines the varying compositions and colour strategies employed in both the LBA and Iron Age objects. Specifically, glass in the LBA was considered to be one of the highest status items attainable, playing an instrumental role in diplomatic gift-giving. When considered with the archaeological information, the significance of these finds at Tall Zirā‛a indicates that this city was a settlement of high status, not primarily a convenient trading stop on the Transjordan route.  相似文献   
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Abstract

The sustainable development model has largely failed to address the social and environmental challenges of the 21st century. True sustainability will only occur when it is valued as a part of the taken-for-granted daily life of individuals and cultures across the globe. This has not yet happened because humanity has not evolved a global consciousness quickly enough to match the global advances in telecommunications and transportation technologies that have created a socially and economically ever-shrinking planet. Travel and tourism contributes to the expansion of global consciousness, although only in a haphazard and unintentional manner. The COVID-19 pandemic is a result of planetary time-space compression and is forcing an expansion in human consciousness that will make humankind better able to address global problems. There will still be considerable diversity on the planet, as now, but the pandemic will stimulate growing numbers of people, businesses and governments to adopt new ways of thinking, behaving and operating that are more closely aligned with the goals of sustainable development. This could be further enhanced if travel and tourism were to adopt the expansion and awakening of global conscious as a fundamental and transformational value in the products and experiences that it offers.  相似文献   
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Résumé  L'article s'attache à dégager le fil rouge qui relie les réflexions de Wilhelm Gottfried Leibniz sur les jeux de société à la théorie des jeux, telle qu'on la trouve dans l'ouvrage de John Von Neumann et Oskar Morgenstern. L'itinéraire décrit passe par les travaux de plusieurs mathématiciens du XVIIIe siècle sur différents jeux de hasard, pour aboutir aux recherches de quelques-uns des fondateurs des mathématiques modernes, comme Ernst Zermelo pour la théorie des ensembles et émile Borel pour la théorie des probabilités. II montre comment une analyse mathématique des jeux de société a débouché sur l'élaboration d'une grille générale d'analyse des phénomènes sociaux. Son cheminement révèle, en outre, la longue parenthèse du XIXe siècle où ce programme s'est trouvé abandonné et esquisse, en conclusion, quelques hypothèses pour l'expliquer. The paper strives to find the clue which links Leibniz' thoughts on parlour games to the mathematical theory of games in John Von Neumann and Oskar Morgenstern.Magna opera the way goes through the works of several XVIIIth century mathematicians on various games of chance to reach the research of some of the modern mathematics founders, as Ernst Zermelo for the sets theory and émile Borel for the theory of probabilities. The paper shows how a mathematical analysis of parlour games ends at a general framework to study the social phenomena. Its development also reveals how this research program has disappeared, all along the XIXth century, and suggests, in conclusion, some tentative explanations of this development. Une version préliminaire de cet article a été publiée dans la revue de l'Association historique des élèves du lycée Henri IV,Jeu et histoire, no spéc.:L'émoi de l'histoire, 25–26, printempsautomne 2002, p. 94–115.  相似文献   
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The palaeobiota from a middle to late Holocene succession in Tom Thumbs Lagoon, N.S.W., Australia, reflects a range of environmental conditions caused by sea-level changes and active estuarine sedimentation. At the base of the succession (~ ?0.4 m AHD) a thin bed, containing molluscs dated at 6.7 ka B.P. by radiocarbon and amino acid racemisation, and foraminifers is indicative of open estuarine conditions. From +0.35 m AHD towards the top of the sequence the charophyte Lamprothamnium succinctum occurs in subrecent deposits. This species is characterised here by statistical measurements, and new characters are described and illustrated. The charophytes record a drop in sea level and the establishment of a lower salinity artificial wetland. The investigation has also established that decalcification in charophytes can be related to acidification produced by the release of organic acids, aggravated after 1928 by anthropogenic pollution.  相似文献   
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Stephen E. Frantzich, Computers in Congress: The Politics of Information
Stephen E. Frantzich, Political Parties in the Technological Age
David H. Freedman and Charles C. Mann, At Large: The Strange Case of the Worlds Biggest Internet Invasion
Kevin A. Hill and John E. Hughes, Cyber politics: Citizen Activism in the Age of the Internet
Dinty W. Moore, The Emperors Virtual Clothes: The Naked Truth about Internet Culture
Tsutomu Shimomura with John Markoff, Takedown: The Pursuit and Capture of Kevin Mitnick, America's Most Wanted Computer Outlaw—By the Man Who Did It
Ziauddin Sardar and Jerome R. Ravetz, (Eds.), Cyber futures: Culture and Politics on the Information Superhighway
Bruce Sterling, The Hacker Crackdown: Law and Disorder on the Electronic Frontier  相似文献   
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