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31.
This paper presents strontium and oxygen isotopic measurements on archaeological human teeth from the ancient Maya city of Tikal, Guatemala, that illuminate the role that migration played in the history of the state. Stable strontium isotope ratios of human teeth parallel the bedrock geology of the location where foods were grown, while stable oxygen isotope ratios reflect the sources of water imbibed, and track geographic variation in the isotopic composition of rain water. Because tooth enamel forms during childhood and is not remodeled during life, we can identify foreign-born individuals at Tikal by their outlying strontium and oxygen isotope ratios. These data indicate that approximately 11–16% of the sampled Tikal skeletons spent their childhood at distant sites. Most of the migrant burials date from the Early Classic period and are high status contexts. Several royal burials demonstrate long distance movement of both males and females, and shed light on the identification of epigraphically-known individuals. Yet, both Early and Late Classic migrants are found in lower status domestic burials. Interaction with distant peers was important in the rise of the Tikal polity, however, immigration from all social tiers contributed to the city’s rapid population growth.  相似文献   
32.
Abstract

This paper describes the process by which objective‐question tests, using an OMR, were introduced into a number of first‐year geography modules at the University of Plymouth. It discusses the rationale for such a move and some of the issues which have arisen. The paper goes on to present the results of various statistical tests, including a comparison of student performance in the objective‐question exams and in the traditional examination essays. A key aim was to determine whether individual students perform consistently across the two forms of assessment.  相似文献   
33.
根据胡适先生日记,对近代贵州籍著名学者谌湛溪先生的名、字、号进行了考证。考证为谌湛溪先生名立,字祖恩,号湛溪。  相似文献   
34.
In this paper, we investigate the potential use of oxygen and strontium isotope ratios (δ18Op and 87Sr/86Sr) measured in archaeological fish enamel as provenance indicators. δ18Op and 87Sr/86Sr were measured in a suite of archaeological carp remains recovered from the Anatolian townsite of Sagalassos dated to the Early Byzantine period (AD 450–650) and compared to that of modern fish, river and lake waters from the Anatolian region. We used sequential leaches in weak acetic acid to remove diagenetic Sr from fossil tooth enamel, monitoring the effectiveness of this approach by measuring the Sr/Ca ratios of the leachates via an isotope dilution thermal ionization mass spectrometry method (ID-TIMS). δ18Op values mostly excluded a riverine origin. 87Sr/86Sr ratios of one fish overlapped with the 87Sr/86Sr signatures of two lakes in the Anatolian region, and at least one lake (Gölcük) could be removed as a candidate owing to a very distinctive 87Sr/86Sr signature not found in any of the fish remains. Most of the tooth samples analyzed could not be assigned a precise geographical origin since the 87Sr/86Sr ratios measured in enamel did not match that of any of the local lakes selected as potential origin. This result suggests that carp may have originated from lakes that have not yet been sampled, although this conclusion is not supported by other archaeological evidence. Alternatively, the lack of correspondence between lakes and fish Sr isotope ratios highlights several possible sources of uncertainties including spatial heterogeneity in 87Sr/86Sr ratio within a lake, the contribution of dietary strontium to the 87Sr/86Sr ratio of fish tooth enamel, and post-mortem alteration of the tooth Sr isotope signal during fossilization. In spite of the high precision of the strontium isotope analyses and the wide range of variation in the surface waters of the Anatolian lakes and rivers, this method may remain limited to distinguishing between lakes situated in regions of bedrock of very distinct age and geology until these sources of uncertainty are more fully investigated.  相似文献   
35.
中国画把题款、印章作为画面布局中不可分割的一部分。清代书画的题款、形式比前代更趋丰富,也更讲究艺术性。  相似文献   
36.
The fate of artifacts incorporated into the ploughsoil as a result of plough damage is considered in terms of two soil mark sites near Winchester, Hampshire. Ploughsoil and subsoil analyses indicate that dispersal of soil material, as a result of ploughing, is limited at the present time and under mould board ploughing techniques. The origin of soil marks underlain only by bedrock is also considered and evidence indicates that such soil marks may appear as groundsurface expressions of ditches which have been removed by plough damage where dispersal of ploughsoil is minimal. Such soil marks may be only short lived if plough depth continues to increase.  相似文献   
37.
Analysis of dental mesowear is a useful tool to examine dietary strategies in ungulates, and provides a palaeoenvironmental proxy at archaeological and palaeontological sites. We examine the distribution of traditional qualitative mesowear variables amongst 33 species of extant African antelope. We also examine the relationship of our dataset with the original dataset of Fortelius and Solounias (2000). We find that confining mesowear analyses to antelope species alone reduces their discriminating power relative to that found in analyses using a broader range of taxa. Variability in mesowear scores along the toothrow suggest that different teeth do not wear equivalently over an individual’s life-time, so it is important to confine comparisons to individual tooth positions for palaeodietary classifications. Mesowear scores from the third upper molar were found to have the greatest discriminating power. Frugivores displayed unique mesowear signatures, suggesting that this trophic guild should be taken into consideration separately in future mesowear analyses. These results have implications which can improve the application and the discriminatory power of mesowear analyses for the determination of the palaeodiets of extinct taxa, and, by extension, their palaeoenvironments.  相似文献   
38.
Cheia (early 5th millennium cal BC) is a prehistoric village in the Dobrodgea province in Romania. Its occupation is attributed to the Early Eneolithic period or Hamangia III phase. The exploitation of animal resources is heavily dominated by husbandry. Although cattle are dominant, they were complemented by caprines, mainly sheep, exploited for tender meat (as highlighted by a 6–12 months age class peak in the mortality profile). Sheep reproduction patterns were investigated through stable isotope analyses in order to characterize the annual rhythms of slaughtering for tender meat acquisition while informing a more general picture on sheep demographical management and animal husbandry at the settlement. Results from δ18O analysis on second and third molar enamel were modeled and compared with modern reference populations. Sheep births took place over less than four months, from late winter to early summer. From this it could be concluded that tender meat could be provided most of the year, excepted over short period in early summer. Finally, comparison of datasets obtained on the M2 and M3 suggests that the M2 presents a more accurate representation of birth seasonality due to lower inter-individual variability in the chronology of tooth growth.  相似文献   
39.
It is suggested with increasing frequency that rather than the industry standard of 1/4 inch mesh, zooarchaeologists use 1/8 inch or even 1/16 inch mesh to insure more complete recovery. These suggestions are based on the implicit assumption that the body size of a taxon and the probability that the remains of that taxon will be recovered are positively correlated. Size of skeletal specimens provides a more direct measure of recovery probability and accounts for the fact that not all skeletal elements in a body are the same size. Frequencies of eight kinds of rodent teeth representing three genera recovered from the Marmes archaeological site in southeastern Washington State, USA, correlate strongly with tooth size despite the use of 1/25 inch mesh screens. Shape of tooth types measured is insufficiently varied to reveal more than a general relationship between shape and recovery frequency. Choice of an appropriate screen mesh should consider the nature of a deposit, research goals, and cost efficiency.  相似文献   
40.
Even though the sun has its peak emission of electromagnetic (EM) radiation in the visible waveband, it still produces a substantial amount of ultraviolet (UV) wavelengths (10–400 nm). However, the largest portion of this emitted energy is blocked by the ozone layer of the atmosphere, only allowing the near-ultraviolet or NUV (comprising the spectral band between 315 nm and 400 nm) to reach the earth's surface. Additionally, sensors acquiring this part of the UV wavelengths must be operated from low altitudes to minimize the effects of strong Rayleigh scattering to which the NUV radiation is subjected. Consequently, this waveband of the EM spectrum is rarely employed in aerial photography and its reflected portion only acquired in very specific applications.  相似文献   
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