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31.
Elimination of extraneous DNA in fossil specimens is of paramount importance for the successful isolation and analysis of authentic DNA; this is especially true when the specimens are of human origin. Bones and teeth are commonly decontaminated with bleach containing the powerful oxidising hypochlorite ion. The procedures involve either submersion in or wiping with the chlorine agent. Using the radioactive isotope Cl36 we showed that submersion of fossil teeth in solutions of small ions such as Cl or hypochlorite, ClO, cause that they migrate right into the pulp. This may lead to the unwanted destruction of authentic DNA. However, using pairs of teeth from the remains of four ancient Europeans (1000–2000 YBP) as well as tooth and hair from an Inuit skull (>300 YBP) we provide evidence that at least some endogenous human fossil DNA survives in powdered pulp/dentin that has been submersed in 2% hypochlorite. Further, we show that powdered pulp/dentin deliberately contaminated with huge amounts of a 414 bp PCR product is effectively decontaminated by suspension in 2% hypochlorite for 5 min. Decontamination of fossil material from teeth may therefore be accomplished by a short direct action of hypochlorite on the powdered specimen rather than less controllable and less efficient external treatments of the whole specimen.  相似文献   
32.
It is of vital importance to be able to sex identify cattle remains to understand the strategies and importance of cattle husbandry in an ancient society. This is usually done from osteoarchaeological assemblages and often relies on measurements of metapodials. The breadth measurement of the distal trochlea is considered an easy way to identify the sex. Bones from males appears to be easily distinguishable from female counterparts, although it has been complicated to find an external control for the morphological results. Here we investigate the reliability of these particular morphometrics for sex identifying cattle bones with molecular genetics. We use a sex discriminating single nucleotide polymorphism in the ZFXY gene and we apply it to DNA from the bones. To keep the fragment size short and suitable for ancient DNA we base the test on a SNP. The test confirms the osteological sex identification in all cases were DNA could be retrieved. This molecular method can also be used when no fragments suitable for osteological sex identification can be found or when the measurements are non-conclusive.  相似文献   
33.
Recent zooarchaeological studies on water buffalo (Bubalus sp.) remains from China and south Asia question the traditional view that water buffalo were first domesticated in Neolithic China over 7000 years ago. The results from several recent population genetic studies of modern domesticated buffalo (Bubalus bubalis) are not consistent with each other, placing the original center of buffalo's domestication in south Asia, southeast Asia, or China. This paper reports a study using an ancient DNA approach to analyze water buffalo remains from Neolithic sites in north China to investigate their affinities with modern domesticated water buffalo, and to shed light on the origin of modern domesticated water buffalo in China.A 169 bp fragment of D-loop mitochondrial DNA was successfully amplified and verified for 13 of 24 bone samples obtained from seven archaeological sites along the Wei River valley in Shaanxi Province, China. The bone samples which yielded positive DNA can be dated to 8000–3600 cal. BP. The phylogenetic analysis of the obtained DNA sequences along with modern water buffalo sequences indicated that the ancient water buffalos were not the direct ancestor of modern domesticated water buffalo. However, the phylogenetic analysis, along with BLAST searches of these ancient DNA sequences, did demonstrate their relatedness to water buffalo more so than to any other bovid species, confirming the existence of indigenous wild (but now extinct) water buffalo species (B. mephistopheles) in ancient China.The DNA analysis of these ancient remains failed to establish direct links between modern domesticated water buffalo (B. bubalis) and indigenous water buffalo (B. mephistopheles) from ancient China. If further DNA studies of more ancient remains from other regions of China confirm the observation of solely indigenous water buffalo species in ancient China, it would suggest modern water buffalo might not have been first domesticated in China.  相似文献   
34.
Attempts were made to detect ancient DNA (aDNA) in samples of 88 human skeletons from eight Neolithic and Bronze Age sites in Greece and Crete. Ancient DNA was absent in specimens from Nea Nikomedia, Lerna, Karaviádena (Zakro), Antron Grave Circle A and Mycenae Grave Circle A. For each of three skeletons from Antron Grave Circle B that were sampled, polymerase chain reactions (PCRs) gave products for nuclear but not mitochondrial DNA, but amplicon yield was low and inconsistent with replicate PCRs failing to give reproducible results. With specimens from Mycenae Grave Circle B, evidence for mitochondrial aDNA was obtained for four of the 22 skeletons that were studied, and at Kouphovouno evidence for mitochondrial and/or nuclear aDNA was obtained with eight of the 20 skeletons that were examined. We conclude that, although aDNA might be present in some Eastern Mediterranean skeletons from later centuries of the Bronze Age, it is not commonly found in material from this period and is likely to be absent from older material.  相似文献   
35.
中国古代社会保障思想与实践初探   总被引:1,自引:0,他引:1  
王国奇 《攀登》2008,27(2):28-31
中国几千年所遗留下来的社会保障思想有许多精华值得我们挖掘和继承,特别是其中的大同均平思想、以民为本思想、兼爱交利思想和仓储后备思想及其实践,尤其值得我们学习和借鉴。吸收古代社会保障中这些行之有效的思想和方法,将有助于我们构建中国特色的社会保障制度,保障基本民生。  相似文献   
36.
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:7,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   
37.
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   
38.
The ancient Egyptians mummified an abundance of cats during the Late Period (664 - 332 BC). The overlapping morphology and sizes of developing wildcats and domestic cats confounds the identity of mummified cat species. Genetic analyses should support mummy identification and was conducted on two long bones and a mandible of three cats that were mummified by the ancient Egyptians. The mummy DNA was extracted in a dedicated ancient DNA laboratory at the University of California - Davis, then directly sequencing between 246 and 402 bp of the mtDNA control region from each bone. When compared to a dataset of wildcats (Felis silvestris silvestris, F. s. tristrami, and F. chaus) as well as a previously published worldwide dataset of modern domestic cat samples, including Egypt, the DNA evidence suggests the three mummies represent common contemporary domestic cat mitotypes prevalent in modern Egypt and the Middle East. Divergence estimates date the origin of the mummies' mitotypes to between two and 7.5 thousand years prior to their mummification, likely prior to or during Egyptian Predyanstic and Early Dynastic Periods. These data are the first genetic evidence supporting that the ancient Egyptians used domesticated cats, F. s. catus, for votive mummies, and likely implies cats were domesticated prior to extensive mummification of cats.  相似文献   
39.
几种防腐剂在古坑木中的吸收量固化率及抗流失性研究   总被引:2,自引:0,他引:2  
不同类型的防腐剂由于化学性质不同,造成在古坑木中的吸收量、固化率及抗流失性有较大差别。为了筛选出适合于古铜矿遗址内古坑木的防腐剂,对木宝等几种防腐剂在古坑木中的吸收量、固化率、抗流失性进行了试验。  相似文献   
40.
珂罗版印刷是一种古老而精妙的平面印刷技术,珂罗版印刷在印刷复杂的书画作品时,特别是在中国古代书画的笔触和墨韵表现上,可以最大限度地体现原作的艺术特色,达到其他印刷手段难以企及的艺术境界。珂罗版印刷与人工设色相结合,提高了人工临摹的工作效率使古老珂罗版印刷更具艺术生命力,成为复制书画文物的最佳手段。  相似文献   
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