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The creation of political landscapes requires the production of places made significant through acts of social remembering. The Gulf lowlands of Mexico exhibit some of the best known acts of social remembering in Mesoamerican prehistory. In this article, we engage political and practice-based frameworks for understanding the process of collective remembering in an examination of how the Olmecs and their successors inscribed their landscape with buildings, monuments, and rock art in ways that invoked the past while reframing it within the needs of their present. In particular, we explore the Olmecs’ memorialization of individuals and events in sculptures and offerings and their creation of narratives through the juxtaposition of sculptures and architecture. We then examine the creation and erasure of collective memory at the regional center of Tres Zapotes as expressed in the biographies of six monuments. We end with a comparison of “metropolitan” and hinterland carvings recorded in regional survey around Tres Zapotes. These examples situate social memory as an evolving entity molded and stretched by competing interests in an ongoing process of conflict and negotiation.  相似文献   
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López-Gappa, J., Pérez, L.M. & Griffin, M. February 2017. First record of a fossil selenariid bryozoan in South America. Alcheringa XX, xxx-xxx. ISSN 0311-5518.

Selenariidae Busk 1854 (Bryozoa) is considered endemic to Australia and New Zealand. Here we describe a new species of Selenaria Busk 1854 from the lower Miocene Monte León Formation (Patagonia, Argentina). Selenaria lyrulata sp. nov. is characterized by autozooids with a lyrula-like, anvil-shaped cryptocystal denticle, opesiular indentations and lateral condyles, as well as avicularia with a shield of fused costae. This is the first record of a selenariid bryozoan in South America.

Juan López-Gappa [] CONICET—Museo Argentino de Ciencias Naturales. Av. Ángel Gallardo 470, C1405DJR, Ciudad Autónoma de Buenos Aires, Argentina; Leandro Martín Pérez [] and Miguel Griffin [], CONICET—División Paleozoología Invertebrados, Museo de La Plata. Paseo del Bosque s/n, B1900FWA, La Plata, Argentina.  相似文献   

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ABSTRACT

The interest in automatic modal parameter extraction techniques has increased significantly in recent years because of the rising demand for Continuous Structural Health Monitoring (CSHM) of civil structures and infrastructures. The wider use of CSHM is related to its capability for early damage detection and therefore to its usefulness for planning maintenance and strengthening interventions. This article presents the main steps followed in creating a robust routine to run on an online basis the first-ever Continuous Vibration-Based Structural Health Monitoring (CVB-SHM) of a large masonry oval dome, i.e., the dome of the Regina Montis Regalis Basilica, also known as Sanctuary of Vicoforte. The procedure uses an output-only stochastic subspace identification method complemented by an automatic analysis applied to identification results, which are typically provided in terms of stabilization diagrams. In this study, the fully automatic procedure also includes a hierarchical clustering algorithm to separate authentic from spurious modes.  相似文献   
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One of the most important pre-Columbian gold assemblages made up of more than one hundred objects from two tombs in the Cauca river valley, Colombia, was studied to obtain archaeometric information. Although several attempts have been made to arrange gold production in time and space from the stylistic point of view, no firm conclusions were possible due to the lack of archaeological contexts. This paper presents first results of a new, fully instrumental approach, in which different analytical techniques, including OM, SEM-EDS, XRF, PIXE, RBS, AMS and X-ray imaging, were applied in order to determine a technological, metallurgical and chronological frame of the so-called Quimbaya Treasure.  相似文献   
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Novel technologies linked to women and men through identity-demarcated tasks and knowledge sets can potentially have differential and even long-term effects on each group. This study follows the trajectory of two significant imports into the coastal western Alaskan system, the firearm and the metal cook pot. These imports had different implications for coastal Yup’ik women and men, young and old. Over time the gun became an integral piece of a man’s tool kit and one that had the potential to boost production and thus a man’s access to status-building. However, these same tools had the potential to undermine the apprenticeship system of male authority. Likewise, the metal cook pot replaced the productive oversight and skill set of elder women’s ceramic production but created paths of independence for younger Yup’ik women. These changes in technology destabilized relative balances of gender and age based status, security, and authority and fashioned new gender and age based social and economic opportunities and limitations.  相似文献   
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New work at Kehf el Hammar Cave provides the first well-dated palaeoenvironmental sequence for the Late Upper Palaeolithic in this region of the northwest Maghreb. The archaeological layers are dated via a combination of AMS radiocarbon and luminescence dating methods. The sequence contains charcoal-rich occupation layers with faunal, human and lithic finds. Local vegetational patterns are reconstructed on the basis of preliminary analysis of the charcoal evidence. Using standard calibration curves the AMS radiocarbon dates are compared with proxy evidence for climatic change from sea core records in the Alborán Sea. These appear to show that the Late Upper Palaeolithic occupation of the region coincides closely with Heinrich Event 1, a period marked by intense aridification and dating to ca. 16,700–17,250 calendar years ago.Les nouvelles recherches dans la grotte de Kehf el Hammar ont permis d’obtenir la première séquence paléoenevironnementale bien datée du Paléolithique supérieur tardif au Nord Ouest du Maghreb. En effet, les niveaux archéologiques ont été datés par le radiocarbone par accélérateur (AMS) et des méthodes radiométriques basées sur la luminescence. En revanche, les paléoenvironnements végétaux ont été partiellement reconstitués à base des premières analyses des charbons de bois. Les dates AMS calibrées ont été comparées aux données climatiques issues des carottes marines dans la mer Alborán. Ainsi, les occupations humaines du Paléolithique supérieur tardif dans la région ont sensiblement coïncidé avec l’événement climatique Heinrich 1. Celui-ci correspond à une période qui a été marquée par une aridification intense entre 16.700 et 17.250 ans (cal.).  相似文献   
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李龙 《史学集刊》2005,(1):106-112
18世纪晚期,美国为维护海上权益与地缘安全,加剧了与英法之间的矛盾。美国在《杰伊条约》中对英国的让步,换取到美英之间十年的和睦,却导致美法关系紧张,美国与法国从同盟走向准战争状态。最终美法危机得以和平解决,但这场准战争深深影响了美国早期的内政和外交。  相似文献   
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