首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 0 毫秒
1.
Opaline phytoliths are important microfossils used in archaeological and ecological research. Relatively little is known about the stability of phytoliths after burial. Under alkaline pH conditions they can dissolve, and mechanical disturbances can cause a loss of their more delicate appendages. Here we present an experimental study of phytolith stability (combination of solubility and abrasion). Modern and fossil phytoliths were extracted from wheat using new methods to minimize dissolution, and by burning in an oven. These assemblages were placed in a solution buffered to pH 10 and maintained under constant temperature and shaking conditions. The silicon concentrations in the solution were monitored once a week for 5 weeks. The phytolith morphologies in each assemblage were determined at the outset of the experiment and after 5 weeks. The results show that there are differences in stability between various assemblages. Modern inflorescence wheat phytolith assemblages are more unstable than those from leaves/stems. Burnt assemblages are less stable than unburnt assemblages, and a fossil phytolith assemblage about 3000 years old is more stable than the modern wheat assemblages. The results also show that individual phytolith morphotypes have different stabilities, and as a result of dissolution and abrasion, some morphotypes may resemble others. This study further shows that archaeological and/or paleo-environmental interpretation of phytolith assemblages may change with the assemblage’s state of preservation.  相似文献   

2.
3.
The origin and evolution of the infectious disease tuberculosis (TB) and its pathogens is still not fully understood. An important effort for a better understanding of the underlying mechanisms of TB evolution lies within the investigation of skeletal and mummified material dating back several thousand of years. In this work, molecular data from mummified and skeletal material from different time periods of the Old World are compared, and the current status of ancient mycobacterial DNA analysis in ancient human remains is discussed, with particular reference to the genetic evolution of human TB. The molecular analysis of material from southern Germany (1400–1800 AD), Hungary (600–1700 AD) and Egypt (3500–500 BC) revealed high frequencies of TB in all time periods. In several individuals from ancient Egypt the mycobacterial DNA could be further characterised by spoligotyping. Thereby, evidence for ancestral M. tuberculosis strains was found in the pre‐ to early dynastic material from Abydos (3500–2650 BC), while typical M. africanum signatures were detected in the Middle Kingdom tomb in Thebes‐West (2050–1650 BC). Samples from the New Kingdom to Late Period tombs (1500–500 BC) were characterised as modern M. tuberculosis strains. In concordance with other studies on ancient skeletal and mummified samples, no evidence for the presence of M. bovis was found. These results contradict the theory that M. tuberculosis evolved from M. bovis during domestication, but supports the new scenario that M. tuberculosis probably derived from an ancestral progenitor strain. Copyright © 2007 John Wiley & Sons, Ltd.  相似文献   

4.
古陶瓷产地判别一直是古陶瓷研究工作的一个重点。为了拓展产地判别的科技研究方法,本研究针对南北方4个不同窑口(越窑、建窑、耀州窑、定窑)的古陶瓷样品,首次结合采用X射线荧光光谱分析(XRF)和热释光(TL)测试分析技术相互印证,测定4个窑口样品的胎釉元素组成和热释光特性,并建立相对应的数据库,相互印证判别古陶瓷样品的产地。数据库的统计分析表明:同一窑口的古陶瓷不仅在主量与微量元素化学组成具有一定的地域特征,其热释光的测量灵敏度也存在地域特征性;不同窑口的古陶瓷可以通过元素组成归类和热释光特性的不同加以区分,结合采用XRF与TL测试分析两种技术可以更准确地对古陶瓷产地进行分析判别。  相似文献   

5.
Archaeologists use survey artifacts to study any number of interesting topics. The focus of this study is to test the usefulness of starch grains and phytoliths found on artifacts recovered during archaeological survey. Phytolith and starch grain analysis was used to determine the level of environmental contamination on three types of medieval ceramics collected during survey work from plowed fields in the parish of Wicken, Northamptonshire, England. The plant residues found on these artifacts were compared with their surrounding soil and with contemporaneous excavated artifacts recovered from under the floorboards of a medieval house in nearby Wyton, Cambridgeshire, England. Through the use of the “piggyback” approach pioneered by Chandler-Ezell and Pearsall, phytoliths and starch grains were systematically removed from the artifacts surface. Residues associated with contamination were removed from the outermost layer of the artifact surface while potentially uncontaminated residues were removed from the innermost layer of the artifact surface. Matching phytoliths and starch grains were found on the outermost surface of the survey artifacts and in the surrounding soils. No phytoliths and starch grains were found on the innermost surface of the survey artifacts suggesting that residues from the surrounding soils did not penetrate into the pores and crevices of the artifacts. The overall results suggest that, although they are preliminary, there is potential for plant residue analysis of survey artifacts.  相似文献   

6.
Crepeline是一种较为薄透的平纹丝织物,在欧美等国的纺织品文物保护中应用较为广泛,尤其对于脆弱丝织品的保护具有非常好的效果。近年来,此种织物在中国纺织品修复中的应用也日渐趋多。由于中国市场上无处购买该材料,为了降低成本并满足中国古代纺织品的修复需求,中国丝绸博物馆与浙江理工大学合作研发了该种修复用织物——绉丝纱。本研究介绍所研发绉丝纱的工艺参数和性能特点,及针对不同类别的中国古代纺织品,采用绉丝纱作为修复材料时的使用方法。即通常将其包覆于纺织品文物表面,以针线缝合的方式固定,并注意缝合时尽量减少针线穿过文物的次数。其包覆的形式,按包覆范围可分为整体包覆与局部包覆;按包覆方式可分为单面包覆、双面包覆及叠加包覆等。研究表明,绉丝纱包覆是一种值得推广的纺织品保护方法,尤其是对已无法承受针线过多穿缝力度的纺织品。如能够解决绉丝纱裁剪后的边缘脱线等细部问题,将会更加扩大其使用的范围。  相似文献   

7.
A method is described for the extraction and identification of opal phytoliths from food residue on the teeth of cattle. Two types of residual food debris were recognized. These yielded varying quantities of silica particles from plants and soil. The application of the identification of silica bodies to enviromental archaeolory is discussed.  相似文献   

8.
A considerable number of molecular studies have provided evidence for the presence of Mycobacterium tuberculosis complex (MTB) DNA in ancient skeletal and mummified material. Moreover first studies on the differentiation of sub‐types of the MTB (M. tuberculosis, M. bovis, M. africanum, M. microti, M. canettii) have successfully been performed on ancient tissue samples. In our present study we extend previous analyses and investigate bone and soft tissue samples from 118 ancient Egyptian mummies and skeletons from the Pre‐ to Early Dynastic site of Abydos and different tomb complexes in Thebes West, which were built and used between the Middle and New Kingdom until the Late Period (c. 2050–500 BC). The samples were tested for the presence of MTB DNA and further identified by spoligotyping. Twenty‐six samples provided molecular evidence for the presence of ancient mycobacterial DNA by amplification of a 123 base pair fragment of the repetitive element IS6110. Out of the 26 positive samples, 12 provided a complete spoligotyping signature, which was compared to an international database. Ten further cases showed an incomplete, patchy hybridization pattern, while in four cases no spoligotyping signature could be obtained. Interestingly, they all show either a M. tuberculosis or M. africanum pattern, but none revealed a M. bovis specific pattern. In the material from a Middle Kingdom tomb (used exclusively between c. 2050–1650 BC) several samples revealed a M. africanum type specific spoligotyping signature, while samples from later periods provided patterns typical for M. tuberculosis. This study clearly shows that spoligotyping can be used for the characterization of members of the MTB in historic tissue samples. In addition, our results do not support the theory that M. tuberculosis originated from the M. bovis type. Copyright © 2004 John Wiley & Sons, Ltd.  相似文献   

9.
A microfluidic device has been developed for the sex identification of ancient DNA samples and works by manipulating liquids within an environment of micrometer dimensions. In this work a range of microfluidic DNA extraction methods were evaluated for their compatibility with ancient DNA samples, and the use of streptavidin-coated super paramagnetic particles to isolate biotin-labeled abasic sites within damaged DNA was shown to be the most reproducible. Polymerase chain reaction-based DNA amplification was possible on the microfluidic device when less than 50 pg of template DNA was added. As a proof-of-principle, powdered bone samples were analysed using the integrated methodology developed. Following conventional capillary gel electrophoresis, two out of the three samples produced positive amplification results and were successfully identified as female. These sex identifications were corroborated by independent Amelogenin, anthropological and Y chromosome analysis. The work reported here is the first step in the development of a complete miniaturized microfluidic system that would enable on-site ancient DNA analysis.  相似文献   

10.
Rice cultivation in parts of the Yangtze valley, eastern China, is thought to date to at least the early Holocene. Using phytolith analysis, sediments from an exposed profile at Qingpu in the lower Yangtze were examined in detail in order to contribute to the growing body of information relating to the history of rice agriculture in the Yangtze delta area. The presence of phytoliths from domesticated rice, Oryza sativa, indicates that rice agriculture was well developed at Qingpu by ca. 2350 BP and may have increased in intensity from ca. 2100 BP. Rice cultivation at Qingpu was comparatively late in relation to other areas in the Yangtze valley, possibly due to the seasonal intrusion of saline waters, while the cultivation of wild rice remained a prominent feature of food production in the area to at least as late as ca. 1800 BP. Results presented here support the existence of a period of overlap, during which both wild and domesticated forms of rice were cultivated, rather than a linear transition from wild to domesticated rice cultivation and the possible influence of environmental factors over farming in an area subjected to frequent flooding.  相似文献   

11.
Accurate identification of the biological sex of ancient remains is vital for critically testing hypotheses about social structure in prehistoric societies. However, morphological methods are imprecise for juvenile individuals and fragmentary remains, and molecular methods that rely on particular sex-specific marker loci such as the amelogenin gene suffer from allelic dropout and sensitivity to modern contamination. Analyzing shotgun sequencing data from 14 present-day humans of known biological sex and 16 ancient individuals from a time span of 100 to ∼70,000 years ago, we show that even relatively sparse shotgun sequencing (about 100,000 human sequences) can be used to reliably identify chromosomal sex simply by considering the ratio of sequences aligning to the X and Y chromosomes, and highlight two examples where the genetic assignments indicate morphological misassignment. Furthermore, we show that accurate sex identification of highly degraded remains can be performed in the presence of substantial amounts of present-day contamination by utilizing the signature of cytosine deamination, a characteristic feature of ancient DNA.  相似文献   

12.
The analysis of short tandem repeats (STRs) is a useful tool in various contexts of ancient DNA research. Main applications are the reconstruction of kinship, identification, and authentication. Here we describe a short amplicon autosomal short tandem repeat (miniSTR) heptaplex system for the amplification of D13S317, D21S11, D18S51, TH01, D5S818, FGA and Amelogenin from highly degraded DNA as an inexpensive alternative to commercially available kits. All primers were newly designed and the amplicon length of all systems is less than 200 bp, with the exception of some rare alleles in the FGA and D21S11 systems. To validate the suitability of this system for typing STRs from human specimens with low DNA preservation we systematically tested it on 20 skeletal samples from four archaeological sites representing different burial environments and time spans since death. Finally, to test the sensitivity of the heptaplex system, we analyzed serial dilutions of control DNA and ancient DNA extracts. Using the system we were able to reproducibly obtain full STR profiles, down to a concentration of 0.06 ng DNA. Even with 0.004 ng DNA partial profiles could be amplified. The accumulated power of discrimination for the six selected STR loci is 0.99999984, plus the option of genetic sex determination through Amelogenin. The tests conducted prove that the system presented is efficient and especially suited for cases where STRs have to be typed and sex has to be assessed from human specimens with highly degraded DNA.  相似文献   

13.
This note describes a simple and inexpensive method for the extraction and counting of opal phytoliths from archaeological and Quaternary sediments.  相似文献   

14.
15.
通古斯巴西古城遗址是新疆重要的土遗址之一,原为唐龟兹驻兵的安西都护府所在地。遗址中曾出土大批文物,对于研究西域的屯垦历史和古代城址布局等有重大意义。为了系统地研究了通古斯巴西古城遗址土的工程特性,在实地调查的基础上,通过室内试验对通古斯巴西古城遗址土的物理、力学、水理和化学性能进行测试。此外,还测定了不同PS浓度加固后遗址土重塑土块抵抗风蚀雨蚀能力的差异,进一步确定了PS的渗透加固措施对土质文物的防风化及雨蚀效果。结果表明,7%的PS溶液防风化抗雨蚀效果要更为显著。研究结果可为PS的施工应用提供依据。  相似文献   

16.
古钱币系列是中国历史经济现象的载体,亦是承载时代进程的脉络与脚印。其见证了不同时期因政权更替的兴盛与衰败。在华夏古代文学宝库里,有关货币的诗话占有独特的重要地位。  相似文献   

17.
Wild rice (Zizania spp.) is an important native grain of north-central North America, with spiritual and subsistence significance to many native peoples. Due to lack of suitable proxies, its past distribution and pattern of use are poorly known. This study demonstrates the diagnostic value of silica phytoliths from Z. palustris as a proxy tool to detect its past occurrence in a variety of paleoenvironmental and archaeological contexts. Our main findings are: 1) Dominant wetland grass species in Minnesota produce phytoliths distinct from Zizania phytoliths; 2) Closely related Leersia oryzoides produces a few Zizania-like phytolith morphotypes; however, these potential confusers can be identified based on 2-D and 3-D morphologies; 3) Z. palustris produces a wide variety of phytolith morphotypes, many of which are only found in certain parts of the plant (e.g., Inflorescence Type 1 from the spikelet); 4) Z. palustris produces 23 locally diagnostic phytolith morphotypes that can be used to determine the presence and abundance of wild rice in modern and paleo lake sediments; and 5) Wild rice phytolith Inflorescence Type 1 is the morphotype most likely to be observed in archaeological contexts, and may be unequivocally diagnostic for the genera Zizania.  相似文献   

18.
19.
The application of crop processing models to macro-botanical assemblages has traditionally been used to interpret past husbandry practices and organisation of labour involved in crop-processing. Phytoliths offer an alternative method of analysis because they are durable in most environments, regardless of whether plant parts are charred, and the identification of plant types and plant parts allows them to be used in much the same way as macro-botanical remains. Indeed macro-remains and phytoliths are complementary datasets for examining the input of plant parts, such as crop-processing waste, into archaeological deposits. We outline crop-processing models in relation to macro-remains and then develop the framework for their application to archaeological phytolith assemblages. Rice and millet processing models are explored in relation to patterns expected in both macro-remains and phytoliths. The utility of these models is demonstrated with archaeological evidence from the site of Mahagara, an early farming site in North-Central India. The results indicate a way to employ phytoliths in archaeology which complements the fragmentary evidence available from plant macroremains.  相似文献   

20.
Ancient Egyptians were buried with the most precious food and drink as sustenance for their afterlife. One of these was Shedeh, the most valued and appreciated beverage in ancient Egypt. The botanic origin of Shedeh remains unclear as no mention of its raw material has survived. Some scholars have proposed that Shedeh was a pomegranate wine, while others, a grape wine. Presented here is the first ever analytical evidence of Shedeh's origin through the analysis of a sample of a residue from an extraordinarily well preserved Shedeh amphora from King Tutankhamun's collection. The previously developed LC/MS/MS wine markers method for archaeological samples was used and our results reveal Shedeh had a red grape origin.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号