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81.
In the present work we attempt to recover endogenous ancient DNA from cereal grains preserved under different conditions: charred, partially charred and waterlogged. A total of 126 grains from naked wheat and 18 from barley from different sites on the Eastern Iberian Peninsula ranging from the beginning of agriculture in the region to the turn of the Common Era, were studied. Two different extraction protocols were used, a standard phenol–chloroform method and a silica-based DNA extraction procedure implemented for artificially charred seeds. Amplifications were directed to three markers: the large subunit of ribulose 1,5 biphosphate carboxylase (rbcL) and the microsatellite WCT12 in the chloroplast genome and the x and y subunits of the high molecular weight glutenin gene (Glu-1) in the nucleus. The first two were used to assess the preservation status of the samples, while with the third we tried to identify the wheat grains at species level. It was possible to obtain eleven positive amplifications in 8 partially charred seeds but only two amplifications of the Glu-1 gene from a single sample of the Early Bronze age were genome-specific. Different contamination sources were identified and reported. Cloning and alignment of sequenced clones showed a correspondence of the amplified fragment to modern wheat D genome haplotypes. This result suggests that the sample corresponds to hexaploid wheat (Triticum aestivum L.), thus being the first ancient DNA evidence to date for the cultivation of hexaploid wheat in the prehistoric agriculture of the Iberian Peninsula. Moreover, obtained results highlight contamination problems associated to the study of ancient archaeobotanical charred seeds suggest that the combination of a silica-based extraction method together with the amplification of specific targets is a good strategy for recovering endogenous ancient DNA from this kind of material.  相似文献   
82.
Radial systems of spoke-like pathways, often termed “hollow ways,” are frequently found surrounding mounded tell sites in northern Mesopotamia and have been explained as the product of a particular set of land use practices involving dry-farming agriculture and intensive ovicaprid pastoralism. Yet while similar subsistence strategies were very common across the Near East throughout much of the Holocene, classic hollow ways have only been previously documented in a small region and articulate almost exclusively with sites of the third millennium BC. This paper presents newly discovered hollow ways in western Syria and southwestern Iran, made possible through analysis of an online database of declassified, Cold War-era CORONA satellite imagery. The association of these previously undocumented ancient roads with archaeological sites dating to the Iron Age, Roman/late Roman and early medieval periods, suggests that the land use practices which produced radial route systems may have been quite widespread. Taking into account the wide geographic and temporal distribution of hollow ways, analysis explores various aspects of the agro-pastoral systems that disparate communities may have shared. Results confirm some aspects existing models of hollow way formation, while offering some refinements in terms of the roles that settlement organization, agricultural land use and pastoral strategies play.  相似文献   
83.
Archaeological studies including stable carbon and nitrogen isotope analyses of bone collagen from human remains have suggested their heavy dependence on terrestrial foods during the Jomon period in the inland central region in Japan. However, it is not easy to quantitatively evaluate the extent of carnivory for archaeological human remains based on the bulk collagen chemistry, because of variable 15N-enrichment factor along the trophic step and background isotopic variations in ecosystems. In order to overcome these problems and more precisely evaluate diets of prehistoric humans who strongly adapted to terrestrial environment, in this study we applied nitrogen isotope analysis of individual amino acids in bone collagen to two inland human populations in the Jomon period. Our results suggest that the two populations were predominantly dependent on the C3-plant-based terrestrial ecosystem and consumed little aquatic resources. Furthermore, their mean trophic positions (2.7 for both cases) are closer to that of the fox (2.8–3.0) rather than those of pure herbivores (2.0–2.2), and show little change over time. These results are the first evidence that inland Jomon populations may have had more carnivorous diets than is traditionally considered.  相似文献   
84.
Recent lidar and pedestrian surface surveys have remapped the well-known Mesoamerican site of Izapa and the surrounding Soconusco piedmont. These data document: 1) occupation from the surrounding piedmont environment, 2) significantly larger estimates of the site's size during both the Formative and Classic periods as well as 3) new architectural features from the monumental site core. Methodological issues are outlined for combining high precision lidar mapping with ground truthing and pedestrian survey that focuses on surface collection of temporally diagnostic artifacts. Results are presented for 670 mounds documented in an area of 43.1 sq km in and around the ancient capital of Izapa.  相似文献   
85.
A correct sex assignment of a given bone or bone fragment is of paramount importance for the archaeologist, anthropologist and in forensic medicine. Discriminant functions, combining several anthropometric measurements obtained from individuals with known sex are useful tools for this purpose, but it is essential to know exactly the sex from which the measures are obtained. This is an easy task in modern populations, but it is problematic in ancient ones, since even when the entire skeleton is available, diagnosis of sex is not 100% accurate. Sexing by genetic methods by amplifying the first intron of the amelogenin gene constitutes a much more accurate method for sexing bones and may be the gold standard for further elaboration of discriminant functions which may serve for sexing new bones dug up in future excavations. With this aim we have genetically sexed 52 (out of 59) tibiae belonging to the prehispanic population of El Hierro, in the Canary Islands, identifying 18 women and 34 men, and then, performed discriminant functions combining several anthropometric variables. These functions show a high accuracy in sex diagnosis (94.2%; area under ROC curve = 0.954 with the best of the functions), so that they allow correct sexing of tibiae or tibiae fragments (only proximal third, distal third or midshaft). Thus, genetic sexing obviates the problem of finding an accurate gold standard for the elaboration of discriminant functions for ancient bones. This method could be applied to other populations of different antiquity and different ethnicity.  相似文献   
86.
Stable isotope analysis of charred archaeobotanical cereal grains has the potential to provide direct evidence of crop growing conditions in the past and to refine palaeodietary predictions. If isotope values of archaeobotanical material are to be considered robust, it is necessary to characterise the compositional changes associated with their charring and burial. This study used a suite of analytical techniques, including FT-IR and solid state 13C NMR, to characterise changes in the biochemical composition of modern einkorn grains with heating at 230 °C for 2 h, 4 h, 8 h and 24 h, encompassing conditions that replicate their undistorted ancient counterparts. The biochemical composition of archaeobotanical charred einkorn grains was also investigated by FT-IR and solid state 13C NMR in order to assess the changes in composition which occur during burial. Results of FT-IR and solid-state 13C NMR show that heating of modern einkorn grains resulted in Maillard reactions between cereal proteins and starch, forming high molecular weight melanoidins, which contain both alkyl and aromatic carbon. Loss of low molecular weight carbon and nitrogen-containing volatiles resulted in a slight but non-systematic increase in the δ13C values and a systematic increase of 0.8‰ in the δ15N values of the charred einkorn grains. Solid-state 13C NMR shows that the ancient charred einkorn grains consisted entirely of aromatic carbon and retained a similar proportion of nitrogen to their modern 24 h charred counterparts, despite a significantly lower concentration of amino acids. This indicates that the amino acid nitrogen in the ancient charred grains was retained in the stable melanoidins whose polymeric structure makes them resistant to subsequent degradation.  相似文献   
87.
郑珍《古本〈大学说〉序》描述了这样一个过程《大学》如何从古本到二程改本,到朱子章句,再到后世诸改本“纷纷益不可胜记”,以至成为笑柄。然见邻水甘秩斋《大学说》,不仅赞叹,以为虽“又一新异本”,实与王守仁《大学古本序》“大义复不相乖忤”。郑珍遂表彰王守仁“复古之功不可没”。守仁复古本之思萌自龙场,经多年思考和反复论证,于正德十三年刻《古本大学序》,正式公布了他表彰古本正当性的观点。  相似文献   
88.
本文对徽派版画中的《古歙山川图》的作者做了比较详尽的考证。  相似文献   
89.
安徽省南陵县江木冲古铜矿冶炼遗物自然科学研究及意义   总被引:5,自引:2,他引:5  
本通过对江木冲冶炼遗址古铜矿、古炼渣、古铜锭及青铜器的对比研究,利用矿床学、冶金学等理论,探索利用自然科学手段解决其输出路线问题,提出了判别其产物(铜锭)的特征微量元素和其它综合判别标志,同时也为青铜器其它矿料来源(尤其锡矿)难题的解决进行了技术路线探索和方法研究。  相似文献   
90.
为了真正实现古陶瓷完整器的元素成分无损分析,就要建造能容纳常规大小古陶瓷样品的真空靶室,以及建立弯曲表面古陶瓷的定量分析方法。本文报道了本实验室QuanX型能谱仪真空靶室改造的整体设计和加工,以及针对弯曲表面古陶瓷样品定量分析的处理方法。大量的测量工作表明所改装的能谱仪完全适应古陶瓷完整器的元素成分无损分析的需要,同时证明古陶瓷样品在较低真空条件下的测量分析是完全无损的;所提出表面弯曲古陶瓷的定量分析处理方法具有简便易行,精确度较高的特点。  相似文献   
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