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61.
Ten years ago, I summarized hypotheses for the abundance of bird wing elements in archaeological sites and rejected the hypothesis that differential preservation caused this pattern in the Pacific Northwest Coast (Bovy, 2002). I also noted that distal wing elements (relative to proximal wings) dominated several assemblages in the Gulf of Georgia sub-region. I re-examine this issue, focusing on behavioral hypotheses for the abundance of distal wings. Ethnographic evidence is used to formulate predictions for the cultural explanations, which are tested using data from the late Holocene Watmough Bay (45SJ280) site, where distal wings comprise 98% of the large duck assemblage (n = 4195). Diving ducks, dabbling ducks, geese, loons and grebes all have more distal wing bones than expected, and were likely caught using submerged nets. The most plausible explanation for the prevalence of distal wing bones is either that only the distal wings were transported back to the sites (perhaps attached to skins) and/or the distal wings were discarded separately during cooking.  相似文献   
62.
Black drink is a native North American caffeinated tea produced from the leaves of Ilex vomitoria. The beverage was an important part of prehistoric Southeastern culture, as it was the only native source of caffeine in North America. The leaves of I. vomitoria were, therefore, a potentially valuable trade resource during the period. As such, the ability to identify archaeological black drink residues is useful to Southeastern archaeologists. In order to determine the plausibility of detecting I. vomitoria in residues, black drink was repeatedly produced in experimental unglazed pottery. The resulting potsherds were buried in several environmental contexts, recovered, and underwent absorbed pottery residue analysis. After two months of burial in three different soil types, plus a control stored in the freezer, caffeine was well-preserved in all sherds, suggesting that caffeine is a potentially useful biomarker for the detection of black drink.  相似文献   
63.
Absorbed lipid residues from 24 seventh‐ to ninth‐century coarseware potsherds from the major Anglo‐Saxon trading centre of Hamwic (Southampton, UK) were analysed by gas chromatography – mass spectrometry (GC–MS) in order to reconstruct the dietary habits of its population. The results show that the vessels were used for preparing ruminant fats and leafy vegetables. In addition, evidence was found for a minor contribution of aquatic foods. Beeswax was found once and most probably relates to a sealing function or to honey. Remarkable features were: (i) the isomeric mixture of octadecenoic acid (C18:1 Δ7,8,9,10,11,12,13,14,15,16) and 8‐ to 16‐hydroxyoctadecanoic acid, and (ii) the co‐occurrence of C17:1, C19:1 and isoprenoid fatty acids. These features were proposed as biomarkers for ruminant and aquatic food sources, respectively. Furthermore, the carbonyl position distribution in mid‐chain ketones was used to identify mixtures of animal‐ and plant‐derived ketones. The paper highlights the difficulty in interpreting complex lipid signatures that show a mixture of various foods, as observed in the majority of the samples. This was linked to the preparation of stews or the recycling of vessels. The results are considered alongside ceramic usewear data and existing data relating to environmental remains recovered from the Hamwic excavations.  相似文献   
64.
A new robust design methodology to control the seismic performance of asymmetric structures equipped with a Single Tuned Mass Damper (STMD) is presented in this article. This design approach aims to control the seismic response of such systems by reducing both flexible-and stiff-edge maximum displacement. The dynamic problem has been investigated in the state space representation showing that the TMD works as a closed-loop feedback control action. A synthetic index to estimate the seismic performance of the main system has been defined by using H norm. Wide-ranging parametric numerical experimentation has been carried out to obtain design formulae for the STMD in order to minimize such a performance index. These formulae allow for a simple design of STMD position and stiffness to optimally control both translational and rotational motion components, whereas two mass devices are generally considered to improve the seismic performance of asymmetric structural systems The effectiveness and efficiency of the obtained design formulae have been tested by investigating the dynamic behavior of the asymmetric structure after being subjected to different recorded seismic inputs.  相似文献   
65.
A selection of plant species that may have been relevant for the Neolithic in the SW Mediterranean have been characterised with pyrolysis gas chromatography mass spectrometry (pyrolysis–GC/MS) in search for molecular vegetation markers. Roots and aerial parts were analysed separately for the following species: Anthyllis cytisoides, Asphodelus cerasiferus, Brachypodium retusum, Cistus albidus, Cistus clusii, Dorycnium pentaphyllum, Ephedra fragilis, Juniperus oxycedrus, Juniperus phoenicea, Olea europaea, Phillyrea angustifolia, Pinus halepensis, Pistacia lentiscus, Quercus coccifera, Rhamnus lycioides, Rosmarinus officinalis, Smilax aspera and Stipa tenacissima; furthermore domesticated plants were analysed, including wheat (Triticum aestivum, Triticum dicoccum, Triticum monococcum, Triticum timopheevi and Triticum turgidum), barley (Hordeum vulgare and H. vulgare Hulled) and legumes (Lathyrus cicera, Lathyrus sativus, Lens culinaris, Pisum sativa, Vicia ervilia, Vicia faba and Vicia sativa). This resulted in 290 potential markers. In addition, the organic matter of surface soils under different vegetation cover has been analysed to test the presence of the potential markers in the soil. Forty-six of the potential markers were detected in the soil organic matter, of which part have not been reported before. The results may be useful for interpretation of the organic matter composition of soils and plant remains, which can be valuable in archaeology.  相似文献   
66.
Located in the historical center of Catania, Italy, in the Civita district, the Bonajuto Chapel is one of the oldest and best-conserved buildings of the city, which has survived the numerous earthquakes that struck eastern Sicily during the medieval and the modern ages, such as those particularly devastating in 1169 and 1693. However, both the date of this small monument, as well as its original use, still remain uncertain, as literary and documentary evidence are scarce and fragmentary. Most historians, analyzing prevalently the stylistic and constructive aspects, interpreted the chapel as a place of worship and assigned its construction to a rather long period of the early Middle Ages, from the 5th or 6th centuries ad to the 8th or 9th centuries ad—the phase during which the island was under the Byzantine domination. The excavations carried out in 1930 to 1939 and the last restoration works (in 2003) have not provided explicit chronological data. Its age determination is considered essential for a better knowledge of the real influence of this domination on the architecture of the Island. Therefore, a multidisciplinary and accurate analysis of the building using the existing bibliography has been carried out also in order to understand the functional and morphological transformations of the chapel during its long life. The thermoluminescence absolute dating methodology applied to some brickwork elements of the construction, has placed the monument chronology in a period of time that is notably shorter than that previously noted here. These new data, with the study of the architectural structure, have made a significant step forward in the knowledge of the chapel history.  相似文献   
67.
马家塬战国墓地是研究西戎文化以及秦戎文化交流的重要考古遗址。在M21墓葬发现了一些附着于铁器表面的矿化纺织品残片。这些矿物外壳保留了比较完整的纺织品形态,是研究早期纺织技术的宝贵资料。为此,本研究采用扫描电子显微镜(SEM)和高效液相色谱-质谱联用技术(HPLC-MS)对矿物纺织品残片的纤维原料进行了鉴定与分析:1)矿物外壳内部的纤维空洞结构形态与桑蚕丝的纤维形态特征相同;2)样品中检出了3组蚕丝蛋白的特征多肽片段。研究结果表明,M21墓葬中的纺织品残片的原料为蚕丝纤维(Bombyx mori)。丝绸的发现表明中原的丝绸成品或者纤维原料已经进入西戎地区,西戎与中原文明的交流更加密切。使用丝绸包裹铁器则表明西戎文化已经受到了一些中原风俗的影响。这一发现填补了马家塬遗址中纺织品研究的空白,不仅为研究秦戎地区的织造工艺和文化交流提供了重要资料,也为矿化纺织遗存中的桑蚕丝残留的鉴定提供了技术支持。  相似文献   
68.
在大众文化的冲击下,学生作文写作在语言上突破了传统语法规范、词语超常搭配、句式随意组合、新词语大胆创造,在内容上冲破了学生作文的传统观念,在结构上打破了记叙文、议论文、说明文、应用文各类文体的写作规范。这些都给写作带来了令人担忧的负面影响。因此,我们急需从学校、教师、社会的角度出发,提出有效的对策。  相似文献   
69.
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   
70.
Textural, mineralogical, and X-Ray fluorescence (XRF) analyses are used as a cost effective method to distinguish for the first time ancient Egyptian and Nubian-style ceramics found in Nubia. Textural and mineralogical data suggest that Nubian-style sherds are mixtures of sand, silt, and clay sediment that is generally finer grained and poorer in quartz than is the sediment mixture used to produce Egyptian-style pottery. Chemical data also establish a significant difference in the amount of chemical variation found within each style population, but nonetheless supports a considerable overlap in the possible provenance of both styles. Observations and data obtained during this study indicate that standardized, Egyptian-style manufacturing was introduced into Nubia under colonialism, without substantially altering the diversity of native methods of production.  相似文献   
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