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41.
We report a successful extraction and sequencing of ancient DNA from carbonized rice grains (Oryza sativa) from six archaeological sites, including two from India and four from Thailand, ranging in age from ca. 2500 to 1500 BP. In total, 221 archaeological grains were processed by PCR amplification and primary-targeted fragments were sequenced for comparison with modern sequences generated from 112 modern rice populations, including crop and wild varieties. Our results include the genetic sequences from both the chloroplast and the nuclear genomes, based on four markers from the chloroplast and six from the nuclear genome. These markers allow differentiation of indica rice from japonica rice, the two major subspecies of Asian rice (O. sativa) considered to have separate geographical origins. One nuclear marker differentiates tropical and temperate forms of subspecies japonica. Other markers relate to phenotypic variation selected for under domestication, such as non-shattering, grain stickiness (waxy starch) and pericarp colour. Recovery and identification of sequences from nuclear markers was generally poor, whereas recovery of chloroplast sequences was successful, with at least one of four markers recovered in 61 % of archaeological grains. This allowed for successful differentiation of indica or japonica subspecies variety, with japonica identified in all the Thai material and a mixture of indica and japonica chloroplasts in the two Indian assemblages. Rice subspecies was also assessed through conventional archaeobotanical methods relying on grain metrics, based on measurements from 13 modern populations and 499 archaeological grains. Grain metrics also suggest a predominance of japonica-type grains in the Southeast Asian sites and a mixture of japonica and indica in the Indian sites with indica in the minority. The similar results of grain metrics and ancient DNA (aDNA) affirm that grain measurements have some degree of reliability in rice subspecies identification. The study also highlights the great potential of ancient DNA recovery from archaeological rice. The data generated in the present study adds support to the model of rice evolution that includes hybridization between japonica and proto-indica.  相似文献   
42.
Recent excavations at the Postclassic period (circa a.d. 1000–1521) mortuary mound of El Cementerio (SON P:10:8), located along the Río Yaqui in central Sonora, Mexico, have documented 105 mortuary features (111 individuals) many of which display elongated intentional cranial modification and several cases of tooth filing. These constitute biocultural traits common across much of Mesoamerica throughout its Prehispanic cultural sequence, which expanded along West Mexico and into northwest Mexico beginning in the late Classic period. The examples from El Cementerio represent the northernmost concentrated expression of these traits and could represent the spread of Mesoamerican/West Mexican identity associated with macro-regional trade and the expansion of the Aztatlán archaeological tradition during the Postclassic period in the region.  相似文献   
43.
ABSTRACT

This article describes the structural design, nonlinear modeling, and seismic analysis of prototype single-storey non-residential steel buildings made of moment-resisting portal frames in the transverse direction and concentric braces in the longitudinal direction. Various design parameters (building geometry, seismic hazard, foundation soil category) and different modeling assumptions (bare frame model, model including cladding elements, ground motions including vertical accelerations, and modeling uncertainties) were considered to investigate their effects on the simulated seismic performance.  相似文献   
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Underwater cultural heritage sites draw thousands of diving tourists lured by the excitement of shipwrecks and the beauty of the marine environment. Through scientific research and interpretation, archaeologists have the opportunity to educate these visitors about the history of the sites and, perhaps more importantly, about the need for preservation. Effective interpretation leads to appreciation of underwater cultural heritage sites as links to our past, rather than simply as mines of ‘treasure’ to be salvaged for personal gain or sites of interest to be consumed by tourists. This paper describes a selection of interpreted maritime sites from the continental US (with specific reference to Florida), the Caribbean, and the Pacific to show how archaeological tourism, specifically shipwreck preserves and heritage trails, can begin to change mindsets, engage emotions, and inform visitors. It also discusses ways in which we can improve upon assessment, monitoring, and long-term preservation strategies after the trails are created and the sand has settled.  相似文献   
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47.
This work focuses on petro-chemical characterisation of the volcanic inclusions often found within the fabric of many ceramic remains from various archaeological sites in eastern Sicily. Petrographic observations and EMP analyses revealed that volcanic glass is strongly influenced by chemical modifications during the firing process, whereas clinopyroxenes keep their original composition unaltered thus constituting an effective tool for provenance attributions. Multivariate statistical analysis of the latter can in fact unambiguously discriminate between different productive areas by comparisons with pyroxenes from volcanics belonging to distinct magmatic provinces. The method proposed here was tested on ceramic remains of different ages and typologies found in southern Italy.  相似文献   
48.
Consilience of genetics and archaeobotany in the entangled history of rice   总被引:3,自引:0,他引:3  
Major leaps forward in understanding rice both in genetics and archaeology have taken place in the past decade or so—with the publication of full draft genomes for indica and japonica rice, on the one hand, and with the spread of systematic flotation and increased recovery of archaeological spikelet bases and other rice remains on early sites in China, India and Southeast Asia. This paper will sketch a framework that coherently integrates the evidence from these burgeoning fields. This framework implies a reticulate framework in the phylogeny of early cultivated rice, with multiple starts of cultivation (two is perhaps not enough) but with the key consolidations of adaptations that must have been spread through hybridisation and therefore long-distance cultural contacts. Archaeobotanical evidence allows us to document the gradual evolutionary process of domestication through rice spikelet bases and grain size change. Separate trends in grain size change can be identified in India and China. The earliest centre of rice domestication was in the Yangtze basin of China, but a largely separate trajectory into rice cultivation can be traced in the Ganges plains of India. Intriguingly, contact-induced hybridisation is indicated for the early development of indica in northern India, ca. 2000 BC. An updated synthesis of the interwoven patterns of the spread of various rice varieties throughout Asia and to Madagascar can be suggested in which rice reached most of its historical range of important cultivation by the Iron Age.  相似文献   
49.
Journal of Archaeological Research - The Late Bronze Age (1700–900 BC) represents an extremely dynamic period for Mediterranean Europe. Here, we provide a comparative survey of the...  相似文献   
50.
Wine has been considered to be mainly red in ancient Egypt linked with the blood of Osiris, the God of resurrection. No text that refers to white wines from the Dynastic Period (3150–332 BC) exists. The first white wine from ancient Egypt was made near Alexandria during the third century AD. To investigate the presence of white wine in ancient Egypt, dry residue samples from King Tutankhamun's amphorae are studied in this article using the LC/MS/MS method for wine markers. This investigation into the existence of white wines in Tutankhamun's tomb allows us to shed new light on the symbolism of white wine in ancient Egypt.  相似文献   
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