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31.
As organic materials, fish and its derivative products are perishable and break down rapidly and ultimately disappear. Unless they include bones or scales, the only means of identifying them in the archaeological record is through the identification of the chemical constituents that are left behind after decomposition. Fish flesh mainly consists of proteins and lipids. Since these molecules are unstable they degrade irreversibly after death or discard, losing a significant part of the original chemical elements, consequently hampering or complicating their identification. In this paper, two main types of fish products are considered: raw, salted or cooked fish, and fermented fish-based products. In the first case, the degradation of the native markers results from chemical post-depositional degradation, and eventually thermal degradation during cooking. In the second case, the biochemical processes involve bacteria that cause the rapid decomposition of fish as part of the process of forming fish sauces, such as Roman garum. To detect and identify fish products we combined experimental archaeology and organic analyses. The identification of the degradation products of cholesterol appeared to provide a strong indicator for detecting the presence of fish sauces. Analysis of samples taken from fish-salting vats located along the Atlantic coast (Marsa, Baelo Claudia, Troia, Kerlaz, and Etel) with samples taken from actual experimental garum sauces made from mackerel (Scomber scombrus), sardines (Sardina pilchardus), and/or oysters (Ostreidae), revealed the presence of common markers of fermented fish-based products. The application of the analytical methodology described here to structures involved in ancient fish sauce manufacture and storage has enabled investigation of the production of the sauces by searching directly for the fish markers on the inner sides of the containers. For the first time the addition of molluscs and fruits in the fish product has been identified as part of the process of manufacturing garum.  相似文献   
32.
During the last restoration of the Fontana di Trevi -Rome (2014–2015), it has been performed a diagnostic investigation to characterize the materials used to build and obtain the colors of the surfaces of some architectural elements of this fountain. According to the restoration teamwork needs, we focussed our efforts on the dome over the central statue of Oceanus, on the bas-relieves on the sides of the dome, and on the cliff where the water flows. Several samples were collected from these elements and therefore, they were subjected to an analytical approach including infrared spectroscopy, optical and scanning electron microscopy. The achieved results indicated the use of red earth pigments on the dome. The same pigment has been revealed on the bas-relieves, although their colors have an additional contribution due to degraded layers. Samples taken from the cliff showed a complex stratigraphy, although a white scialbo has been identified as original layer, testifying the intentions of the authors in term of color rendering. This information was essential for the restores in order to choose the proper intervention procedure for each investigated surface. The research testified the importance of an integrated diagnostic analysis to preserve the original colours of monuments and building.  相似文献   
33.
ABSTRACT

The employment of timber pegs in timber structure joints is a widespread technology in the field of timber frame building in the United States, where the Timber Frame Engineering Council has published a special Standard to supplement the National Design Specification for Wood Construction. The authors have been studying the possibility of supplementing the Eurocode 5 design formulas, thought for timber joints with metal connectors, with specifications needed for a reliable design when employing timber pegs. The field of application envisaged is that of restoring timber structures and results obtained until now are quite encouraging. In this step of the research, more attention has been paid to deformation process: fir and chestnut samples have been tested to determine their dowel-bearing behavior with steel and ash timber peg while double-shear plane joints made of the same wood species, and fastened with steel as well as timber pegs, have been analyzed.  相似文献   
34.
35.
Very small, green colored, partially mummified remains of a perinate individual were found buried in a ceramic pot with a copper coin in the Late Medieval cemetery of Nyárl?rinc-Hangár út (“Nyárl?rinc 3. lel?hely”) in southern Hungary. The remains must date back to the second half of the nineteenth century AD. In this paper; we present data gathered in a series of multidisciplinary investigations targeted to the partially mummified remains (ind. no. 14426) and two other non-mummified perinates (ind. no. 10662 and no. 14336) possibly buried under similar circumstances in the cemetery. Besides standard macromorphological and stereomicroscopic examinations, we compared Cu concentrations in the remains using ICP-AES and mapped Cu concentration changes using μXRF. The partially mummified perinate showed the highest Cu concentrations, while the individual buried without a possible Cu source showed the lowest. Body parts in the closer proximity of the copper coins always showed higher concentration. The mummified individual showed 497 times higher Cu values than average, and even the perinate buried without copper coin measured higher than the otherwise normal Cu content of the soil. Extremely high Cu values may be related to the corrosion of the coins included in the burials. Mummification must have been facilitated by copper deriving from the coins. Uneven Cu concentrations and only partial mummification of one of the individuals refer to the importance of other environmental factors involved in a possible quasi-natural mummification process. However, the Nyárl?rinc perinate burial no. 14426 may be the first solely copper-driven mummification case ever reported, and hopefully, more cases are to appear in the future.  相似文献   
36.
We investigated the contribution of freshwater resources to the diet of seven Late Mesolithic hunter-gatherers (ca. 5300–7000 BC) from Northern France and Luxembourg using stable isotope ratios. In addition to the carbon and nitrogen stable isotope ratios (δ13C, δ15N), we explored the potential of the sulphur isotopic ratios (δ34S) to detect and quantify the proportion of protein derived from aquatic foodstuff. In only two sites, animal remains from an associated settlement were available and subsequently examined to decipher the isotopic differential between terrestrial and freshwater resources. The quantification of their relative contribution was simulated using a Bayesian mixing model. The measurements revealed a significant overlap in δ13C values between freshwater and terrestrial resources and a large range of δ15N values for each food category. The δ34S values of the aquatic and terrestrial animals were clearly distinct at the settlement in the Seine valley, while the results on fish from Belgium demonstrated a possible overlap in δ34S values between freshwater and terrestrial resources. Local freshwater ecosystem likely contributed to ca. 30–40 % of the protein in the diet of the individuals found in the Seine settlement. Out of this context, the isotopic signature and thus contribution of the available aquatic foods was difficult to assess. Another potential source of dietary protein is wild boar. Depending on the local context, collagen δ34S values may contribute to better assessment of the relative contribution of freshwater and terrestrial resources.  相似文献   
37.
The aim of this article is to focus on the technology of archeological plasters at Teotihuacan (Central Mexico), from the Classic Period (200–650 A.D.), focusing in the study of Teopancazco, a neighborhood center in the city. Petrographic and chemical analyses by OM, SEM-EDS, and LA-ICP-MS were conducted to characterize samples from different constructive phases and sectors of the neighborhood center, to determine the provenance of the raw materials employed in the manufacturing (e.g., volcanic glass shards) and to assess whether a shift occurred in the manufacturing of plasters and in the procurement strategies of raw materials during the different phases. The results of the analyses show that almost no changes occurred in the making of the plaster during more than four centuries and allow us to consider the presence of a technological style in their manufacture, which is characterized by the making of plaster by mixing lime with volcanic glass shards, which in the case of Teopancazco were derived from the Altotonga (Veracruz) magmatic system. The data at our disposal suggest that this style was developed in Teopancazco and later introduced throughout the city of Teotihuacan in the Early Xolalpan phase (A.D. 350), although we still do not know whether the provenance of the raw materials is the same. The wide distribution of this technological tradition could be due to the technological properties of the materials and/or the influence of the intermediate elite who ruled over Teopancazco. The paper confirms that the study of material culture and technology sheds light on broader cultural aspects of ancient societies.  相似文献   
38.
The animal remains found at the fourteenth–fifteenth century Hof van Leugenhaeghe are crucial to reconstruct the life of the noble inhabitants, as all buildings were destroyed with the construction of a later estate on the property called the Blauwhof. The diet confirms the high social status of this nobility with the suspected consumption of pig skulls, a possible sign of wealth in late-medieval Flanders. Other signs of a noble diet are found as well: juvenile cattle, a diverse spectrum of game, partridge and grey heron. The observed pattern of a wealthy diet is consistent with the zooarchaeological assemblages found at other noble sites in late-medieval Flanders.  相似文献   
39.
Quaternary stratigraphy and sea level changes have been extensively investigated in many areas of the Mediterranean. However, numerical dating of coastal deposits and the associated paleoenvironmental information are limited for the coasts of Cyprus, principally based on radiometric and radiation-exposure geochronological techniques on fossils which bear a range of limitations and uncertainties. As such, optically stimulated luminescence (OSL) dating techniques are deemed to be the most suitable in direct dating of the coastal sediments of Cyprus. In the southeastern Cyprus, coastal dunes (aeolianites) now forming elongated ridges appear as morphological features running parallel to the current shoreline presenting an indicator of sea level and climate changes of great paleoenvironmental significance. We present our first chronological results for the exposed aeolianites and underlying littoral deposits formed along the southeastern coastal Cyprus ranging from 78.4 ± 9.9 to 56.2 ± 7.4 ka. The post-infrared–infrared stimulated luminescence (pIR-IRSL) revealed that dune formation took place during the marine isotope stages (MISs) 3, 4, and possibly 5a. Late Holocene reworking is proposed for a distinctively isolated dune with an age of ~1.3 ka ago. This study also showed that pIR-IRSL dating of feldspars may be a reliable alternative to quartz OSL dating when the quartz luminescence characteristics are unsuitable.  相似文献   
40.
The taphonomic analysis of avian remains from Sarakenos Cave reveals that, contrary to previous suggestions, many bird bones excavated there represent food remains of the Eagle Owls rather than humans. The conclusion is based on the presence of traces of digestion, beak and claw punctures, and indirect evidence that includes relative preservation of particular elements, species composition, the lack of cut marks, and the absence of numerous traces of burning. Specimens with medullary bone and traces of digestion indicate that the owls killed breeding females in spring. Since it is unlikely that owls shared the cave with humans at the same time, it supports the notion based on archeological evidence that human groups did not inhabit it permanently.  相似文献   
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