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71.
Although use-wear analysis of prehistoric stone tools using conventional microscopy has proven useful to archaeologists interested in tool function, critics have questioned the reliability and repeatability of the method. The research presented here shows it is possible to quantitatively discriminate between various contact materials (e.g., wood, antler) using laser scanning confocal microscopy in conjunction with conventional edge damage data. Experiments with replica and prehistoric tools suggest the quantitative method presented here provides valid functional inferences and is flexible enough to accommodate other relevant sources of data on tool function.  相似文献   
72.
The presence of vascular grooves on the shafts of femora and tibiae was scored for a sample of human remains from a mass burial at Tell Majnuna, Syria, dated to the early fourth millennium bce . In the sample of 140 femora and 64 tibiae, many of which were damaged or fragmented, the grooves were most common on the femoral midshaft (31/108 = 28.7%) and on the proximal and middle shaft of the tibia (10/45 = 22.2 and 14/54 = 26.0%, respectively). For femoral midshafts, the difference in mean cross‐sectional size and shape indices between bones with and without vascular grooves was checked with multivariate analysis of variance for a sample of 51 bones. The presence of grooves appeared to correspond significantly with higher mean values of both indices. As the shape index is interpreted as an indicator of the level of terrestrial mobility and the size index may be used for sex assessment, it is possible that vascular grooves occur more frequently at the femoral midshafts of men and more active individuals, and thus they may be cautiously interpreted as another activity‐related trait. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   
73.
This article presents the results of a project to 3D laser scan and digitally model 14 watercraft from the Qatar Museums collection, comprising a range of regional vessels: most had not been surveyed previously. The project used the resulting point clouds generated 2D naval lines and orthographic records of the vessels in their current condition, and photorealistic 3D digital models for gallery display. This case study provides illustrative examples of the intermediate stages and final outputs. It assesses the pros and cons of 3D laser scanning as a survey technology for nautical scholars in terms of the time, cost, and skillset, as well as logistical considerations. It also compares the accuracy of traditional hand survey methods.  相似文献   
74.
医用螺钉在手术中得到大量的使用的同时,因其质量事故频发,患者对质量鉴定要求越来越迫切。我们借助光学显微分析、电子显微分析技术、X射线荧光能谱分析等微量物证分析技术。从微观角度对螺钉断裂原因进行了质量鉴定.  相似文献   
75.
In this study, detection success rates were evaluated for cultural remains that were detected manually based on interpretation of digital terrain models (DTM) derived from airborne laser scanning data and with a resolution of 1, 5 and 10 points m−2. The group of cultural remains included charcoal kilns, charcoal pits, hollow-roads, various pits, house foundations, tar kilns, grave mounds and pit-falls. The effects on the interpretation success of different types of cultural remains and their physical properties were studied: size, shape and elevation difference showing that the detection success rates varied considerably. The main tendency was that large cultural remains with clear geometrical shape (ovals and circles) and large elevation difference were much more successfully detected and classified compared to the smaller ones, especially those without a clear geometrical shape. The study also showed that it was the identification of the larger structures which profited most from an increased resolution of the DTM, and it was of no help to increase resolution in order to improve the identification of the irregularly shaped cultural remains.  相似文献   
76.
Lee, D.E., Kaulfuss, U, Conran, J.G., Bannister, J.M. & Lindqvist, J.K., August 2016. Biodiversity and palaeoecology of Foulden Maar: an early Miocene Konservat-Lagerstätte deposit in southern New Zealand. Alcheringa 40, xxx–xxx. ISSN 0311-5518.

This paper highlights the biodiversity and palaeoecology of the 23 million year old Foulden Maar, the first Konservat-Lagerstätte deposit described from New Zealand and a key site for reconstructing early Miocene Southern Hemisphere terrestrial ecosystems. The 1000-m-diameter, ca 200-m-deep Foulden Maar volcanic crater lake was a closed system with anoxic bottom waters, capturing and preserving in exquisite detail organisms from the lake and adjacent rainforest. The fossils include numerous leaves, flowers with in situ pollen, fruits, seeds, fish and arthropods. Surrounding Foulden Maar was an evergreen, Lauraceae-dominated notophyll vine forest with a diverse understorey, lianes, epiphytes and mistletoes. Diverse pollination and seed dispersal modes are evident. Fish include larval to adult stages of articulated specimens of Galaxias, some with preserved soft tissue and a species of eel resembling Anguilla. The arthropod fauna comprises ca 20 families in the orders Araneae (spiders), Plecoptera (stoneflies), Odonata (dragonflies), Isoptera (termites), Hemiptera (true bugs), Diptera (true flies), Coleoptera (beetles), Trichoptera (caddis flies) and Hymenoptera (wasps, ants and bees), representing faunas typical of soil, leaf litter, forest floor or freshwater habitats. Many fossil taxa have close relatives in the extant New Zealand biota; others are now locally extinct. Coprolites containing quartz sands sourced from outside the lake indicate the presence of volant birds, presumably waterfowl. The Foulden Maar Lagerstätte is crucial for reconstructing Miocene lake and forest ecosystems in New Zealand, particularly the terrestrial arthropod component.

Daphne E. Lee [], Department of Geology, University of Otago, PO Box 56, Dunedin, New Zealand., Uwe Kaulfuss [] and Jon K. Lindqvist, [], Department of Geology, University of Otago, PO Box 56, Dunedin, New Zealand; John G. Conran [], Australian Centre for Evolutionary Biology & Biodiversity and Sprigg Geobiology Centre, School of Biological Sciences, Benham Bldg DX 650 312, The University of Adelaide, SA 5005, Australia; Jennifer M. Bannister [], Department of Botany, University of Otago, PO Box 56, Dunedin, New Zealand.  相似文献   
77.
This article reports the mapping of the stones, including marbles and brick masonry, used for building the facade of the medieval Church of St. Nicholas (XI century ad), one of the most interesting churches in Pisa, due also to the nearby famous octagonal bell tower. Mapping of stone materials was performed using a computer-aided design (CAD)/geographical information system (GIS) software package for storing and processing spatial information of the ashlars, obtained using three-dimensional (3D) laser-scanning data, combined with high-resolution images, and stone-to-stone observations. Based on collected data, the facade of the Church of St. Nicholas appeared mostly composed of rocks belonging to the metamorphic Tuscan sequence, quartzites, and marbles from Mt. Pisano area. Other types of rocks were also observed, as black limestones quarried at some kilometers northwest from Pisa in the Monti d’Oltre Serchio area, white Apuan marbles and Macigno sandstones. Conversely, intarsia appeared mainly made up of serpentinite and, subordinately, red limestones laid in white Apuan and Mt. Pisano marbles.  相似文献   
78.
Samples of mortars and stone of Portal de ses Taules from the Renaissance city walls of Eivissa (16th century) were characterized using thermal analysis— thermogravimetry and derivative thermogravimetry (DTG)—x-ray diffractometry, and scanning electron microscopy. The granulometric fraction of particle size <63 μm was selected as representative of the binder, while the fraction 0.5–1 mm was taken as representative of the aggregate in order to characterize mortar samples. The results show that local materials were used. Lime was the main component of most of the samples tested. Thermal analysis revealed the hydraulic nature of the lime mortars. High amounts of sodium chloride were found in the samples analysed.  相似文献   
79.
A methodology is described for the analysis of Holocene charcoals excavated from a rock shelter in the Lubombo Mountains of northeast Swaziland. Scanning electron microscopy was used to compare these with modern reference woods. Of the ancient material 96·6% could be identified, in some cases at specific level. It is in such a subtropical area, where the woody flora is so rich, that assemblages of local taxa can be used in palaeoclimatic reconstructions. The changing taxa indicated by the charcoal fragments from the rock shelter clearly reflect minor shifts in Holocene climate, from moist to dry and back to moist in recent times. This is of relevance to the fluctuations in Stone Age populations in southern Africa. The wider use of such evidence to complement other palaeoenvironmental and archaeological data is advocated.  相似文献   
80.
The detailed elevation model based on airborne laser altimetry (AHN) proved to be a reliable tool to detect well-developed Celtic field systems, characteristic arable plots of the Iron Age. They were detected in the central part of the Netherlands, where only a limited number of Celtic field systems have been recognized in the past. Most of these previously detected systems were identified in the northern part of the Netherlands or in the southern part, but not in this zone. About 1200 ha of well-developed systems could be identified by AHN in the central part of the Netherlands, of which only 136 ha were registered as an archaeological monument. Another 335 ha of archaeologically identified Celtic field systems were not accepted or recognized by AHN, because they were morphologically less well-developed. Most of the around 1050 ha new discoveries occur in rough vegetations and forested areas, and can hardly be identified with previously used geodetic methods and aerial photography. Less well-developed or preserved systems were even more extensive and remnants were traced as fossil arable layers below plaggen soils or on lower slopes incorporated in mediaeval reclamations. The newly identified Celtic field systems, therefore, can be considered as remnants of much larger areas once covered with these arable plots. In the central part of the Netherlands, the estimated area once covered was at least around 4500 ha, more than enough to supply 10,000 people with cereals. Well-developed Celtic field systems started to develop in the late Iron Age with formation intensifying during the early Roman Period. The central part of the Netherlands is situated just north of the river Rhine, the former boundary of the Roman Empire, the Limes. The newly discovered extent of Celtic field systems will have influenced the interaction between different cultures on the border of the Roman Empire in the early Roman Period, about which very little is known. This perspective underscores the need for an integrated conservation policy and in-depth research through excavations in the near future.  相似文献   
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