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Research into the family of the Counts Swéerts-Sporck raised doubts regarding their biographical data, particularly concerning a child who died in 1817, later identified as Philipp Swéerts-Sporck, and his siblings Joseph and Barbara. These were alleged to include a pair of dizygotic twins, but DNA could not be used to clarify their relationships. Carbon and nitrogen isotopes were therefore measured in their first permanent molars, whereas Philipp's biological age was estimated based on his skeleton. Philipp died at an older age than the written sources claim; an isotopic similarity was found between Joseph and Barbara, but Philipp differed.  相似文献   
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The presence of the osseous remains of at least four mules in a garbage dump at the Roman fort of Biriciana near the town of Weißenburg, Upper Bavaria, dating to c. 160 AD, raised the question as to whether mule breeding was already performed to the north of the Alps during the Middle Roman Empire, or whether these animals still had to be imported from the Mediterranean. Serial analyses of the dental enamel and dentine of a lower fourth premolar and the surrounding alveolar bone of a mandible of a mule in terms of stable strontium isotopic ratios of the apatite, and stable carbon and oxygen isotope ratios of the structural carbonate, were carried out to test whether this individual moved long distances during its lifetime. Since isotopic ratios obtained by serial analysis can be correlated with consecutive ontogenetic stages, it can be assumed that this particular individual experienced significant changes in terms of diet and environmental parameters after its eighth year of life. These changes included a period of residence in a region of high altitude, most likely the Alps considering the location of the Roman fort where the mule was found. The isotopic data obtained do not contradict the assumption that this animal was bred and raised in northern Italy, to frequent later in its adult life the Alps and finally perish at Biriciana/Weißenburg. Copyright © 2008 John Wiley & Sons, Ltd.  相似文献   
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Mexican prehistory is characterized by migration and population isolation in its earliest phase, followed by later inter‐population cultural interactions, such as politics and trade. While shared, common morphological variants are often informative about recent population events, rare trait variants have not been widely investigated to see whether they might be informative about earlier events. Here, we consider populations that show several rare variants at frequencies high enough to warrant such an investigation. Examining past population structure can help us understand population interactions across different periods of time, levels of migration, and population isolation/drift. Multiple‐origin populations may have more variation, including more and higher rates of rare traits. We examined maxillary lateral incisors in 1117 dentitions from 76 samples of Preclassic/Classic and Postclassic pre‐European contact Mexico and the American Southwest for the prevalence of rare lateral incisor variants. Variants observed included barrel, congenital absence, interruption groove, mesial marginal bending, peg, reduced, supernumerary, and talon teeth. The most common variant overall is interruption groove. Central Mexico, Huasteca, and the Lowland Yucatan region samples present the highest overall number of incisor variants. Higher frequencies of single unusual traits are commonly found in samples from smaller populations, while samples from larger population centres show a greater range of these rare variants. We investigated to see whether the pattern of rare incisor variant frequencies reflected early or later population history by comparing similarity/distance matrices and factor model matrices using Mantel tests and Generalized Procrustes analysis. Results show a weak relationship with the Postclassic period and shared migration/language and trade interaction models. We suggest that later cultural interactions have acted to mask earlier population history. Research on serial founder effects should be approached multiregionally and across time, to avoid missing inter‐region biological relationships. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
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The structure of brine films in grain boundaries of halite has been the subject of much controversy over the past 20 years; although a number of innovative methods have been developed to study these structures, much is still unknown and fundamental information is missing. In this study, we investigated different methods of plunge‐freezing to vitrify the brine fill of grain boundaries for natural salt polycrystal. This was followed by a preliminary study of the 3D morphology of a vitrified grain boundary in a natural rock salt sample with a focused ion beam (FIB) excavation system. We have shown that brine‐filled grain boundaries in rock salt can be efficiently well frozen when dimensions are less than about 1 mm. Coupled with an ion beam tool, cryo‐SEM allows 3D observation of the well‐frozen grain boundaries in large volumes and high resolution. Initial results of brine‐filled natural halite grain boundaries show non‐faceted crystal–brine interfaces and unexpectedly low dihedral angles at room temperature and pressure.  相似文献   
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朱晗  赵荣  郗桐笛 《人文地理》2013,28(3):70-73,19
作为典型的线性文化遗产,大运河遗产完全具备文化线路的基本要素,对于它的保护应建立在对其性质、价值和特点进行充分研究和评估的基础上。根据大运河在各个时期开挖的规模、航运和繁荣的程度不同,大运河的建设过程可以被划分为三个阶段:隋前被视为中国大运河体系的初步形成阶段;隋唐至北宋可以被认为是大运河得以进一步完善和发展阶段,也可被视为是大运河繁荣的一个阶段;元、明、清被认为是中国大运河实现南北直航和再次繁荣的阶段。安徽段大运河是隋唐大运河(通济渠)的重要组成部分,其保护工作必须先开展资源调查,弄清家底,然后进行科学研究,并从整体上编制保护规划,努力延续运河遗产的真实性和原真性。同时,运河遗产保护还需形成统一协调的管理机制,做好展示和阐释,鼓励沿线社区公众参与遗产保护等。  相似文献   
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