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11.
Excavations at the archaeological site of Encosta de Sant'Ana (Lisbon, Portugal) uncovered a mid-Holocene buried alluvial soil associated with early Neolithic occupation layers. Routine laboratory analyses and micromorphological observations were undertaken on the soil material. Humic acids from its Ab horizon, as well as Neolithic ecofacts, were radiocarbon dated. The dates obtained indicate that soil was formed between c. 8.0 and 6.0 cal ka BP and that the pedological evidence fits the record of the North Atlantic Holocene IRD events (“Bond events”) and the so-called “Holocene climate optimum”. The geoarchaeological record reveals that Neolithic inhabitants settled upon a stable surface, still affected by soil formation that was suddenly interrupted by slope wasting, probably in correspondence to Bond event 4, at c. 6.0 cal ka BP.  相似文献   
12.
老化丝织品的氨基酸分析研究   总被引:2,自引:0,他引:2  
为了解氨基酸分析能否成为有效的研究丝织品老化原因及检测丝织品老化程度的方法,选用经光老化、热老化和水解老化的现代白色丝织品和出土于湖北、内蒙古、青海的古代丝织品为样品,将称好的样品用6mol/L的HCl在110℃恒温烘箱中水解22小时,然后用美国Waters公司产的氨基酸自动分析仪进行分离及检测,根据色谱图中各个氨基酸的峰面积得出各个氨基酸的百分含量。实验结果表明,光老化和热老化时,丝织品强度的损失与酪氨酸含量的降低呈线性关系;水解老化时,丝织品强度的损失与天门冬氨酸含量的降低呈线性关系。结果说明,氨基酸分析从分子水平上给出各种老化的特征及老化程度,无论是对于机理研究还是对于老化程度的判定,都很有实用意义。  相似文献   
13.
Analyses of sterols and biological studies have shown that a Roman defensive ditch was also a cesspit. The plant debris includes wheat fragments dispersed from defecated bread or other farinaceous food. These techniques may reveal ancient diets in a detail previously impossible to achieve.  相似文献   
14.
Gas chromatography–mass spectrometry (GC–MS) and bulk carbon isotope determinations have been performed on samples (‘cemented organic residues’, charcoal, sediment and fire-cracked rock) excavated from 12 slab-lined pits from various locations in Arctic Norway to test the premise that these archaeological features were used for the extraction of oil from the blubber of marine mammals, such as seal, whale and walrus. A wide range of lipid compound classes were detected especially in the cemented organic residues and in the charcoal samples. The presence of long-chain unsaturated and isoprenoid fatty acids together with oxidation and thermal alteration products of unsaturated acids such as dicarboxylic acids, dihydroxyfatty acids and ω-(o-alkylphenyl)alkanoic acids suggests that these features were used for marine oil extraction at elevated temperatures. Notably the location of the hydroxyl groups in the dihydroxyfatty acids provides a record of the positional isomer of the precursor fatty acid and allows confirmation that 11-docosenoic (cetoleic) acid, the most abundant C22:1 isomer in marine oil, was a major component of the original lipid. Further information was provided by the presence of long-chain fatty acyl moieties in surviving triacylglycerols and the presence of cholesterol. A fungal metabolite, mycose (trehalose), was found in all samples apart from a fire-cracked rock and points to microbiological activity in the pits. Bulk isotope analysis conducted on the ‘cemented organic residues’ is consistent with modern reference samples of blubber and oil from seal and whale. These data provide clear analytical evidence of the function of slab-lined pits in the archaeological record and suggest widespread exploitation of marine mammals for producing oil for heating, lighting and myriad other uses in the past.  相似文献   
15.
This paper reports on a methodological study carried out in order to propose a cleaning procedure to remove stains produced by bronze corrosion products on surface of limestone (namely travertine); the procedure is effective and more environmentally friendly than the methods commonly used today. Several copper complexing or chelating agents were considered, including three amino acids and compared with some ion exchange resins. After a first laboratory phase on pure copper products and on artificially stained quarry samples, the optimized procedure was tested on the pedestal of a bronze statue in the Sapienza campus, in Rome. Colorimetry and ICP/OES were used to evaluate the efficiency of the cleaning procedure.  相似文献   
16.
A public latrine in the ‘Imperial Baths’ of Sagalassos was transformed into a dump site in the early Byzantine period. Several layers of urban waste, including ceramics, bones, glass and perhaps excrements were deposited on the floor. Faecal biomarker analyses and archaeobotanical analyses were conducted to reconstruct the history of the room. 5β-stanols of human origin, such as coprostanol, were found in the sewage channels together with mineralised plant remains, indicating a human faecal context. The botanical remains are furthermore representative of the Roman diet of the Sagalassians. Soil layers, deposited on top of the latrine floor and dating to the early Byzantine period, contained herbivore derived 5β-stanols, such as 5β-stigmastanol and epi-5β-stigmastanol. Additionally, a clear predominance of epi-5β-stanols over 5β-stanols showed that the animal dung has been subject to composting. In this period, the former latrine was clearly used as a manure production site which is further confirmed by stratigraphic evidence of large amounts of urban waste artefacts, which were commonly collected together with manure before application on the fields. The results of the present study support the theory that off-site potsherd scattering can be used as a proxy for manuring events. Additionally, the data show key evidence for vertical migration of 5β-stanols and presumably also for the leaching of bile acids.  相似文献   
17.
Ancient preserved molecules offer the opportunity of gaining a deeper knowledge on their biological past. However, the development of a proteomic workflow remains a challenge. The analysis of fossils must involve a low quantity of material to avoid damaging the samples. In this study an enhanced proteomic protocol was applied to 5-milligram samples of about 130,000-year-old mammalian bones ranging from the end of the Middle Pleistocene up to the earlier Upper Pleistocene, excavated from Scladina Cave (Sclayn, Belgium). Using sequence homology with modern sequences, a biological classification was successfully achieved and the associated taxonomic ranks to each bone were identified consistently with the information gained from osteomorphological studies and palaeoenvironmental and palaeodietary data. Amino acid substitutions on collagens were identified, thus providing new information on extinct species sequences and helping in taxonomy-based clustering. Considering samples with no osteomorphological information, such as two fragments of bone retouchers, proteomics successfully identified the families providing paleontologists new information on these objects. Combining osteomorphology studies and amino acid variations identified by proteomics, one of the retouchers was potentially identified as belonging to the Ursus spelaeus species.  相似文献   
18.
Analysis of absorbed organic molecules in groundstone could provide a valuable means to study resource use and processing in antiquity. The following study analyzed extracts from the surfaces of several central California milling tools to assess whether organic residues remained from prehistoric resource processing. It also sought to determine which source identification methods are likely to be successful at providing information about the type, or even the specific identify, of resources that were processed. Lipids (primarily fatty acids) were analyzed using GC–MS and the presence of phenolic compounds was assessed with UV-Vis spectroscopy. Milling surfaces were compared to previously broken surfaces from the same tool with the assumption that both surfaces had been exposed to similar post-depositional conditions. Results supported the presence of ancient residues in milling tools. A higher concentration of fatty acids was recovered from milling surfaces than paired broken surfaces. Furthermore, measurable amounts of azelaic acid (an oxidation product of some unsaturated fatty acids) were present in most milling surfaces, but not in broken surfaces. However, results also indicated that environmentally absorbed lipids formed a significant portion of the total lipid content. Thus, it is suggested that future analyses employ a biomarker approach, rather than criteria based on ratios of common fatty acids, to identify sources of organic residues in prehistoric milling tools.  相似文献   
19.
The remains of the preserved ice body from the Kwäd?y Dän Ts'ìnch? discovery were recovered from a retreating glacier in the Tatshenshini-Alsek Park, British Columbia in August 1999. Despite the remote location 80 km inland, bone collagen stable isotope analysis indicated that the individual spent much of his life in a region rich in marine foods (δ13C −13.7‰ and δ15N +17.9‰). Since finds of such bodies are exceptionally rare we undertook detailed lipid analyses in order to assess their preservation and determine whether they might provide new insights into the individual’s dietary life history. Molecular fingerprinting and compound-specific carbon isotope analysis were performed on individual lipids extracted from his bone (turnover approximately ≥1 year) and skin (turnover approximately several weeks). A considerable abundance was observed of C12:0, C14:0, C16:0, C16:1, C18:0 and C18:1 fatty acids (FAs), cholesterol and hydroxy FAs (the latter being decay products). Most unusual was the presence of long-chain hydroxy FAs (LCHFAs), 10- and 12-hydroxyeicosanoic acid and 10- and 12-hydroxydocosanoic acid, in the bone. The latter components are most likely the products of microbially mediated hydration of the double-bonds of C20:1 and C22:1 FAs, the latter almost certainly originating from the consumption of a largely marine-based diet. A suite of three isoprenoidal lipids, phytanic acid, pristanic acid and 4,8,12-trimethyltetradecanoic (TMTD) acid, was also detected supporting the notion of a significant marine component of the diet for a substantial part of his life. In contrast, the skin lipid composition was dominated by C16:0 FA, with lower abundances being observed of the marine LCHFAs and isoprenoidal compounds, suggesting reduced reliance on coastal marine foods in the last period of life. This interpretation is supported by the enhanced marine dietary signal observed in the bone than skin FA δ13C values.  相似文献   
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