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91.
A number of blocks of resinous materials were found in the cargo of a 12th‐ to 13th‐century shipwreck, discovered in the late 1980s in the Java Sea near the Indonesian islands of Sumatra and Java and excavated in 1996. These well‐preserved blocks presumably were trade materials used for religious, medicinal, cosmetic, decorative or practical purposes. Such materials, derived from plants and termed exudates, generally include frankincense, myrrh, ‘gum benjamin’, liquidambar, dragon's blood, dammar, copal and amber. The source of the cargo resin could not be determined from the site. Investigation by nuclear magnetic resonance (NMR) spectroscopy has revealed that the molecular structure corresponds to that of modern resin from the plant family Dipterocarpaceae, known in trade as dammar and closely resembling Group B copal and amber. Other molecular classes of exudates are excluded. Such materials are not present in the Middle East, which then cannot be their source. The NMR spectra differ from those of Group B samples from Australia, Papua New Guinea and Indonesia, but resemble those from India or Japan. The spectra indicate that the saline environment had a similar effect on the molecular structure to heating and aging.  相似文献   
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93.
In the present study a simple method is described for obtaining 3D digital models of petroglyphs of different sizes and characteristics and its usefulness, in the study of this cultural heritage, is evaluated. For this research we used low-cost photogrammetric software and consumer-grade digital cameras, without any other surveying techniques. In order to test this methodology, three field research studies were carried out in Galicia (Spain).  相似文献   
94.
The application of solid state electrochemistry techniques for the characterization and dating of leaded bronze objects is described. Characteristic voltammetric signatures of copper and lead corrosion products were used as markers of more or less prolonged corrosion periods. The proposed methodology was applied to samples from the Roman archaeological sites of Valeria (Spain) and Gadara (Jordan), Roman and medieval sites in Xàtiva (Spain), and modern statuary exhibited outdoors, on the campus of the Universitat Politècnica of Valencia, Spain, covering a time interval between the fourth to second century bc and the 20th century ad . For such samples, the ratio between the signals for copper and lead corrosion products decreased monotonically with the corrosion time. This variation was modelled on the basis of thermochemical and kinetic considerations, the experimental data being consistent with a potential rate law for the corrosion process.  相似文献   
95.
The World Health Organization endorses the study of diseases from the perspective of the Determinants of Health (DH), that is, the circumstances in which people are born and raised, the environment in which they grow up and age and their lifestyle. The aim of this study is to analyze the spatial behavior of the prevalence of asthma in Aragon, a Mediterranean region in Spain, under the DH approach. The methodological process entailed building a spatial database collating asthma prevalence as dependent variable, and lifestyle, socioeconomic, and climate indicators as explanatory factors, and then evaluating the spatial variability of the relationships by combining the Principal Component Analysis (PCA), Multiscale Geographically Weighted Regression (MGWR) models and cartographic design techniques. MGWR evidenced spatially varying relationships operating at different scales. Lifestyles seem closely tied to the prevalence of asthma in most of the study area while urban functionality and local climate patterns seem to boost prevalence rates in some specific enclaves. Consequently, the social and environmental conditions that characterize the study area translate into several DH scenarios modulating the spatial distribution of asthma. This differential DH behavior detected by local regression models is relevant to guiding and refining public health decision-making.  相似文献   
96.
International Journal of Historical Archaeology - This article summarizes the progress and current state of underwater archaeology in Colombia over the past three decades. It also presents the...  相似文献   
97.
Cenizo, M.M., Tambussi, C.P. & Montalvo, C.I., iFirst Article. Late Miocene continental birds from the Cerro Azul Formation in the Pampean region (central-southern Argentina). Alcheringa, 1–22. ISSN 0311-5518.

The oldest known birds from the Cerro Azul Formation are described, including the oldest records for the genera Eudromia and Nothura (Tinamidae), Milvago (Falconidae), Pterocnemia (Rheidae) and an undetermined Tyrannidae. The first remains of Phorusrhacidae for this formation are reported and a specimen previously referred to the giant teratorn Argentavis magnificens is reassigned to this family. We outline and update the current knowledge of the groups studied herein. The palaeornithological record from the Cerro Azul Formation is congruent with palaeoenvironmental inferences previously drawn from mammalian assemblages recovered from this unit, which point to the existence of open environments, possibly xerophyllous shrubby steppes, perhaps with some trees. These records are the first indications of a typically Pampean bird fauna at the end of the late Miocene in central-southern Argentina.  相似文献   
98.
Palynofloras from an outlier of Tertiary sediments in the One Tree Hill area north of Adelaide are nonmarine and correlate with similar assemblages from Middle Eocene North Maslin Sands from Maslin Bay and Golden Grove. Although there are similarities with time-equivalent Lower Nothofagidites asperus Zone palynofloras in the Gippsland Basin, a number of species in the South Australian palynofloras do not extend below the Late Eocene in the Gippsland sequences. This indicates earlier appearances for these species in southcentral Australia. The sediments overlie a highly weathered bedrock palaeosurface, indicating that a phase of significant weathering occurred prior to the Middle Eocene. A number of selected taxa are illustrated and their distribution in the palynofloras is discussed. Two new species, Proteacidites mildenhallii and Proteacidites parrawirrensis, are described and one species, Rhoipites byfieldensis, is emended.  相似文献   
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100.
Joan Torras, professor of the strength of materials at the School of Architecture of Barcelona (1871–1910), considered the beam of equal strength not only as a structurally extremely efficient beam, but also as beautiful because of its ability to reflect the material’s strength. Torras’ structures have left their special mark on Barcelona and on the work of his most illustrious students: Rafael Guastavino in the United States published similar structures, but it was Antoni Gaudí and Josep Maria Jujol who transfigured them mimetically for Barcelona’s Park Güell and Tarragona’s Metropol Theatre, respectively. These examples will show how an expressive gesture can thoroughly transform a “technical form” into an “artistic form”, a fact that inevitably recalls the wisdom of classical Greek mimesis.  相似文献   
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