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Anna Sandak Jakub Sandak Magdalena Zborowska Włodzimierz Prądzyński 《Journal of archaeological science》2010
Archaeological wood, as most of natural materials, is slowly decomposing on the archaeological site due to various biological factors. Rapid and accurate estimation of the degradation level is extremely important for optimal restoration and conservation. The goal of this research was to verify the effectiveness of Fourier transform near infrared (FT-NIR) spectroscopy for archaeometry. The important advantage of the NIR spectroscopy is its accuracy, simplicity and ability to perform very high number of tests without needs of any destruction to the workpiece. Five oak pieces of the archaeological wood collected from waterlogged sites in Poland have been used. Cellulose and lignin contents, as well as crystallinity and the degree of polymerization were measured with standard reference methods and compared to the contemporary wood. The near infrared spectra represent all the physical/chemical changes of the wood due to waterlogging. This technique was successfully validated in rapid estimation of the cellulose and lignin contents. The method explored in this research might be a novel tool assisting experts in evaluation of the degradation state of archaeological and historical wooden materials. 相似文献
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The present study focuses on investigations carried out in the Late Vistulian succession of the Warta River deposits (central
Poland) in which a horizon of subfossil trees was excavated. Prelim-inary conclusions on time record and past environmental
conditions of a forest existence determined from radiocarbon dating, pollen analyses and geological evidence appear promising
with view of tree-ring chronologies. 相似文献
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The cliff in Ustka is an active one. The area is one of the most eroded sea shores of the Polish coast. The Ustka Cliff mainly consists of Holocene sandy deposits, but its basis is built of glacial till and clay. Field search allowed to recognize the structure and sedimentary conditions of Holocene deposits exposed in the cliff. A comparison of dating results obtained for fossil soils and peat as well as aeolian deposits, using 14C and TL methods, respectively, with available literature records is presented. The evaluation of results obtained allowed to define three main dune-forming phases for the first time for this part of the Polish coast. During the research studies new data on the processes and environmental conditions was gained and the development of structure of the area during the last 10 thousand years was reconstructed. The analysis of available data from other sections of the southern Baltic coast shows that results obtained are age similar to those determined for the ?eba Spit. The research is part of a project concerning the geomorphology of the Ustka Bay. 相似文献
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Joanna Moncrieff 《Journal of the history of the neurosciences》2013,22(1):30-46
When “antipsychotic” drugs were introduced into psychiatry in the 1950s, they were thought to work by inducing a state of neurological suppression, which reduced behavioral disturbance as well as psychotic symptoms. This view was reflected in the name “neuroleptic.” Within a few years, however, the idea that the drugs were a disease-specific treatment for schizophrenia or psychosis, and that they worked by modifying the underlying pathology of the condition, replaced this earlier view, and they became known as “antipsychotics.” This transformation of views about the drugs' mode of action occurred with little debate or empirical evaluation in the psychiatric literature and obscured earlier evidence about the nature of these drugs. Drug advertisements in the British Journal of Psychiatry reflect the same changes, although the nondisease-specific view persisted for longer. It is suggested that professional interests rather than scientific merit facilitated the rise of the disease-specific view of drug action. The increasing popularity of atypical antipsychotics makes it important to examine the origins of the assumptions on which modern drug treatment is based. 相似文献
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Joanna Ostapkowicz Christopher Bronk Ramsey Fiona Brock Caroline Cartwright Rebecca Stacey Mike Richards 《Journal of archaeological science》2013
This paper presents 19 AMS radiocarbon dates from nine pre-Hispanic Caribbean (Taíno/Lucayan) wooden sculptures in the British Museum collections, provenanced to Jamaica, Hispaniola and the Bahamas. Together with strontium isotope results and wood and resin identifications, these data build a material and chronological context for some of the most recognised examples of Taíno art – from duhos (ceremonial seats) and cemís (free standing depictions of deities, ancestors and spirits) to canopied stands used to hold hallucinogenic drugs during the cohoba ceremony. Each sculpture widens our understanding of Caribbean carving traditions, stylistic variation, chronologies and material resource utilisation. A group of three sculptures recovered from Carpenters Mountains, Jamaica, carved by AD 1300 and brought together as a ceremonial ‘set’, each appear to have had their inlays renewed over a century later, suggesting long-term use. Three key examples of the main Caribbean duho categories (high-back, low-back and extended), provide insights into the diversity of styles present in the region post-AD 1100. The British Museum's corpus enables an exploration of regional styles, and potentially the work of individual artists. 相似文献
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Chen-Yang Cai Adam Ślipiński Di-Ying Huang 《Alcheringa: An Australasian Journal of Paleontology》2013,37(4):488-493
Cai, C.-Y., ?lipiński, A. & Huang, D.-Y., 31.3.2015. The oldest root-eating beetle from the Middle Jurassic of China (Coleoptera, Monotomidae). Alcheringa 39,488–493. ISSN 0311-5518.Jurorhizophagus alienus gen. et sp. nov., a new fossil root-eating beetle, is described and figured based on an exceptionally well-preserved impression fossil from the Middle Jurassic Daohugou beds (ca 165 Ma), Inner Mongolia, northeastern China. It represents the earliest fossil Monotomidae known to date. Jurorhizophagus can not be assigned to either of two subfamilies Monotominae or Rhizophaginae based on the unique combination of many unusual characters, including an 11-segmented antenna with a 3-segmented club, the presence of a distinct frontoclypeal suture and transverse pronotum with a median longitudinal groove. The discovery of a new genus from the Middle Jurassic highlights the antiquity of Monotomidae and provides new information about the phylogenetic relationships between Monotomidae and its allied families.Chen-Yang Cai [caichenyang1988@163. com], Di-Ying Huang [dyhuang@nigpas. ac. cn] (corresponding author), State Key Laboratory of Palaeobiology and Stratigraphy, Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences, Nanjing 210008, PR China; Adam ?lipiński [adam. slipinski@csiro. au], Australian National Insect Collection, CSIRO National Collections Australia, GPO Box 1700, Canberra ACT 2601, Australia. 相似文献