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1.
The presence of DNA has been demonstrated in the cell nuclei of an ancient Egyptian mummy fragment. When extracted, this DNA proved to be degraded to a considerable extent and chemically modified. However, the preservation of nucleic acids in this specimen suggests that applying recombinant DNA techniques to the study of ancient mummified tissues might prove to be a fruitful future area of research.  相似文献   
2.
In order to carry out strontium (Sr) isotope analysis, glass artefacts from South Asia were sampled with portable laser ablation (pLA), a relatively novel sampling technique that leaves damage invisible to the naked eye. Subsequently, thermal ionization mass spectrometry (TIMS) was used to obtain Sr isotope ratios after sample dissolution and separation. In this study, the goal was twofold: to determine whether the measurements of Sr isotope ratios were impacted by using a portable laser as a sample tool; and to assess the pertinence of using Sr isotope ratios to provenance Indian glass. Despite a deterioration in the precision of the measurement of the Sr isotope ratios for artefacts sampled with pLA compared with the traditional sampling method, the Sr isotope ratios of certain Indian glass are so different that this does not affect their separation but a comparison of data sets obtained using standard methods and pLA might be challenging.  相似文献   
3.
利用三维扫描技术获取兵马俑残片的三维点云数据,结合Geomagic Studio和Hypermesh建立高精度的兵马俑足踝残片三维实体网格模型。通过基于ABAQUS的重力作用下的有限元分析,研究足踝部分的Von Mises应力和变形特征,以确定足踝处的受力薄弱部位。为进一步探究模型各残片的最佳点云简化比例,采用点云简化模型进行相同工况的有限元分析,以验证点云简化的可靠性。结果表明:结构在重力作用下可保持安全稳定的状态,相对薄弱部位位于左腿足踝处;对于大部分残片,其最佳简化比例在60%~70%,简化后可有效缩短模型实体化处理时间;采用简化模型得到的有限元结果,其最大Mises应力相比于原始模型的误差小于15%,且应力云图和变形图形状接近,模型简化具有可靠性。  相似文献   
4.
The results obtained from the multi-analytic compositional characterization of ceramic pastes and paints of the Santa María style, from the El Bolsón valley (Belén Department, Catamarca Province, Argentina), are presented here. This pottery style had a wide regional distribution in Northwestern Argentina between ca. 1000 and1600 ce and is characterized by its complex iconography painted in black, cream and red. The analyses show that the containers correspond to the technical tradition of using grog temper and suggest that its manufacture involved a double firing process. This reveals a new practice for the time.  相似文献   
5.
Knowledge about the Inca measurement system is based on information from the colonial chronicles and modern studies of the 16th-century Quechua dictionaries. Based on those texts, we can presume that the Incas used an anthropometric system of measurement adopted from the proportions of the human body. Using cosine quantogram analysis and statistical verification, it is possible to verify the existence of the measurement system used by the Inca architects. For this purpose, a measurement series of architectural and water infrastructure elements were collected from 3D point cloud of the Chachabamba and Machu Picchu settlements in Machupicchu National Archaeological Park.  相似文献   
6.
Avian egg-shell occurs fairly commonly on archaeological sites, particularly in alkaline deposits. It is rarely studied in detail. Egg-shell structure is described briefly below and features which may be of value for identification purposes are discussed. Egg-shells from 14 archaeological sites are tentatively identified as goose, domestic fowl, duck and guinea fowl. It seems likely that confident identification should ultimately be possible using a combination of features. This should yield information complementary to osteological evidence for the history of the utilization of birds and their eggs.  相似文献   
7.
One of the most intriguing questions for archaeologists studying clay artefacts concerns technologies employed in their manufacture and whether standardization can be demonstrated through traditional ceramic analysis. Visual comparisons and mechanical measurements have been used to determine correlations and infer standardization. Using a laser multi‐line scanner and software developed to quantify Hausdorff distances between vertices in 3D surfaces, we analysed sample collections of figurines and moulds from Belize, Mexico and Honduras. The results indicated that this procedure was a more precise indicator of common source and standardization in moulded clay artefacts. This method provided data relevant to assessing the scope of ancient trade networks and the nature of social and economic relationships that existed among the ancient inhabitants of Mesoamerica.  相似文献   
8.
The original fineness of coins is very important information that can help us to understand the commercial situation in a wide historical context. This paper deals with a comparison of analytical methods suitable for the evaluation of the actual and original fineness of coins based on a detailed case study of a medieval coin sample. Both non‐destructive (i.e., scanning electron microscopy/energy‐dispersive X‐ray spectroscopy, X‐ray fluorescence, atomic force microscopy and hydrostatic weighing) and destructive (i.e., inductively coupled plasma – mass spectrometry and the Volhard titration method) techniques were used. The original fineness can be also deduced from knowledge of the internal structure of the coin (limited miscibility of copper and silver). A new analytical method based on a combination of a micrograph of the metallographic cross‐section with consequent image analysis was developed for determination of the original fineness. The proposed approach is relatively simple and provides reliable values. Sample heterogeneity and its impact on the determination of fineness are also discussed.  相似文献   
9.
The restoration of paintings on elements in cultural heritage buildings (fundamentally, churches) involves two structural problems: capturing the geometry of the construction element and its development. In many cases, the geometries are regular (e.g., cylinders, spheres, elliptical domes). However, there are cases in which the elements cannot be adapted to any known geometry, much less one that can be mathematically developed. The development of surfaces becomes essential for the restoration of paintings over “flat elements” (over which work is performed on the ground) that are subsequently transferred to the real surface (ceilings). The mathematical transformations that allow regular geometries to be developed are widely known (cartographic projections). However, when the geometry is irregular, there is no development. This study presents a new methodology based on differential rectification and its application for the development of oculi in the Los Santos Juanes Church (Valencia), whose geometry is completely irregular both in shape and as a result of construction defects (and damage caused by fire). The present study focuses on the restoration of paintings damaged by fire.  相似文献   
10.
Pan, Z., Zhu, M., Zhu, Y. &; Jia, L., August 2017. A new antiarch placoderm from the Emsian (Early Devonian) of Wuding, Yunnan, China. Alcheringa 42, 10–21. ISSN 0311-5518.

Wufengshania magniforaminis, a new genus and species of the Euantiarcha (Placodermi: Antiarcha), is described from the late Emsian (Early Devonian) of Wuding, Yunnan, southwestern China. The referred specimens were three-dimensionally preserved in black shales, allowing a high-resolution computed tomography reconstruction of anatomical details. The new euantiarch is characterized by a large orbital fenestra, an arched exoskeletal band around the orbital fenestra and a developed obtected nuchal area of the skull roof. Maximum parsimony analysis, using a revised data-set of antiarchs with 44 taxa and 66 characters, resolves Wufengshania gen. nov. as a member of the Bothriolepididae, which is characterized by the presence of the infraorbital sensory canal diverging on the lateral plate, and the nuchal plate with orbital facets. New analysis supports a sister group relationship between Dianolepis and the Bothriolepididae. Luquanolepis, a coeval euantiarch from the neighboring site of the new form, is referred to the Asterolepidoidei and represents the basalmost and earliest member of the Asterolepidoidei.

Zhaohui Pan* [], Min Zhu* [], You’an Zhu? [] and Liantao Jia [] Key Laboratory of Vertebrate Evolution and Human Origins of Chinese Academy of Sciences, Institute of Vertebrate Paleontology and Paleoanthropology, Chinese Academy of Sciences, PO Box 643, Beijing 100044, PR China. *Also affiliated with University of Chinese Academy of Sciences, Beijing, 100049, PR China. ?Also affiliated with Uppsala University, PO Box 256, 751 05 Uppsala, Sweden.  相似文献   
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