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1.
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Intervertebral chondrocalcinosis (calcification of intervertebral discs and associated structures) may arise from a variety of causes. This work presents a discussion of intervertebral chondrocalcinosis and the identification of its most probable cause in skeletal remains, using as a case study a skeleton of an elderly male from medieval Ipswich, UK. The skeleton is examined using gross observation and radiography, and the intervertebral calcifications are subject to chemical analysis. In addition to intervertebral chondrocalcinosis (which has resulted in ankylosis of lumbo‐sacral segments), lesions identified include chondrocalcinosis at some synovial joints, various soft tissue calcified bodies, and severe osteoarthritis particularly at the gleno‐humeral joints. Interpretation of the results of the chemical analysis of the calcified deposits is complicated by diagenesis, but they are most consistent with apatite and/or whitlockite. Arriving at a most probable cause of the lesions in this case is difficult, but it is tentatively suggested that ochronosis may be the best diagnostic option. Copyright © 2008 John Wiley & Sons, Ltd.  相似文献   

3.
Dental pathologies and enamel defects in East Asian hominins have rarely been reported. Here, we systematically document and describe a suite of enamel defects in the Xujiayao juvenile maxilla, an East Asian hominin from the early Late Pleistocene that may represent an unknown hominin lineage. In addition, we determine the chronology of growth disruptions represented by matched linear enamel hypoplasias, evaluate the long‐held hypothesis that the large brownish pit on the I1 is evidence of dental fluorosis and assess the utility of micro‐computed tomography (micro‐CT) techniques in analyzing enamel defects. With the use of binocular microscopy, scanning electron microscopy (SEM) and micro‐CT imaging techniques, the Xujiayao teeth were found to exhibit a high number of pit‐form defects seldom seen in the fossil record. By matching the timing of linear enamel hyperplasia across multiple teeth, a minimum of five developmental disruptions were identified, indicating that the Xujiayao juvenile experienced several growth disturbances during its short lifespan. Our SEM and micro‐CT analyses suggest that the large pit on the I1 is an enamel hypoplasia due to its morphology and pre‐eruptive enamel thinning. It is not a post‐eruptive fluorotic pit, and there is no evidence of chalkiness or opacity associated with dental fluorosis. The micro‐CT technique made it possible to verify the presence of enamel hypoplasia and to more precisely quantify defect dimensions, especially in unerupted teeth and shallow hypoplasias that are difficult to detect by binocular microscopy or SEM. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   

4.
The site of U?urlu on the island of Gökçeada (Imbros) is the earliest known Neolithic settlement within the Aegean Islands (c.6800–4500 cal. BC). In total, 37 pits, associated with a rich variety of artefacts as well as human and animal bones were excavated in the Late Neolithic and Early Chalcolithic levels of the site (c.5900–4500 BC). The pits belonging to the early sixth millennium BC levels of U?urlu were small and located within the houses that seem to have gone through multiple episodes of house destruction and renovation rituals. During the late sixth millennium BC, this area became the focus of extensive pit‐digging activity, when large pits involving rich variety of artefacts were set within the courtyard of a special building (Building 4). Among the pits, a collective human burial pit (P188) incorporating the remains of 11 individuals and another pit (P52) involving a partial human skeleton were also found. From a comparative point of view, the construction techniques of these pits, their spatio‐temporal relations as well as their associated archaeological artefacts resemble the Anatolian and Near Eastern Neolithic practices of house destruction and renovation cycles, which are activities related to the ancestor cults of the region. We argue that all of these practices reflect public events during which social relations were negotiated through the agency of place. The differences observed during the sixth millennium BC at U?urlu reflect the changing concepts of place and society in the immediate aftermath of the Neolithic Process, when interactions with the Balkans as well as the Aegean intensified in this region.  相似文献   

5.
We present a new method to assess use‐wear formation processes of pounding tools used to break bones based on a combination of conventional microscopy, optical 3D surface measurements obtained with a confocal microscope and GIS analysis. The method involves 3D alignment and 3D surface change inspection techniques along with a surface morphometric characterization and 2D spatial pattern analysis, to measure the spatital distribution of significant changes in surface topography of pounding tools. Our results show that microscopic changes can be detected in the surfaces of hammers and anvils after bone breakage activities are performed. Use‐wear on the active elements (hammers made on basalt and quartzite) occurred over a larger area than was observed on the passive element (quartzite anvil), but the latter often exhibited deeper modifications. Tool surfaces generally developed smoother topography with increased use, but grain microfracture also appeared with greater frequency over time. This methodology offers highly accurate and statistically robust analyses of microscopic use‐wear traces that can be applied to the analysis of archaeological pounding tools.  相似文献   

6.
One of the aims of the 5‐year Iranian/Italian project for Persepolis, called ‘From Palace to Town’ was to contribute to the conservation of the stone monuments of the imperial site. As part of the activities dedicated to this purpose, a diagnostic study was carried out. Various aspects were considered: petrographic characterization of the stone, forms and factors of decay, and in situ testing of suitable conservation treatments. The present paper reports on the unexpected results of the study on the finishing of architectural surfaces. The results obtained on a limited, but nevertheless significant, number of samples collected from the monuments of the imperial Terrace, allow us to state that the dark grey limestone used for several (or many?) monuments was covered on purpose with a thin, fine whitish layer containing fluorapatite, as major component, and calcite. It is highly probable that the fluorapatite was obtained from calcined animal bones and that slaked lime was used as a binder. Further evidence for this is the discovery of a kiln with the remains of calcined bones and, nearby, a waste pit with animal bones containing fluorapatite. A second white layer, obtained with barium sulphate, was detected in one of the samples beneath the external, earthy encrustation. It could be perhaps interpreted as the remnants of a polychrome finishing.  相似文献   

7.
This paper develops a method for analyzing surfaces with a focus on their qualitative similarity. The method describes the qualitative similarity between surfaces defined in the same region in both quantitative and qualitative ways. Given a location and a direction in the region, mathematical functions evaluate the similarity between surfaces. Integrals of the functions with respect to location and direction give quantitative measures of the total similarity between surfaces. A qualitative method uses spatial characteristics shared by surfaces: α‐peak regions, α‐pit regions, and ß‐monotonic lines. α‐peak and α‐pit regions indicate approximate locations where many surfaces have peaks and pits, respectively. ß‐monotonic lines are line segments on which most surfaces change monotonically in the same direction. Those spatial objects reveal the spatial structure shared by surfaces. The method is applied to the analysis of the daily market structure of a supermarket in Japan as an empirical study.  相似文献   

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Sampling of deposits at the Queens Hotel site, York, produced a substantial number of small terrestrial vertebrate remains from the Anglo–Scandinavian features. By studying bone surface modification, fragmentation and skeletal completeness as taphonomic indicators, it was possible to demonstrate that the assemblage had resulted from two very different modes of accumulation and deposition. Refuse pits situated within the boundaries of the tenements had acted as accumulators of the fragmented and abraded small mammal and amphibian bones that existed as a sub‐surface death assemblage within the local environment. In contrast, the excellent preservation and skeletal completeness of numerous frogs recovered from the basal fill of a wooden well could be accounted for by their direct entry into the burial environment as a result of pit‐fall trapping. This paper also discusses the implications that the temporal and spatial variation in deposition demonstrated by the micro‐faunal remains has for the reconstruction of local ecological and environmental conditions within this site, and for other such sites. Copyright © 2001 John Wiley & Sons, Ltd.  相似文献   

10.
The results of investigations performed on more than 23,500 mammoth bones and teeth in Northern Eurasia from 2003 to 2013 with the aim of revealing traces of enzootic diseases are presented here. The study focused on the Late Pleistocene “beast solonetz” sites (i.e. mineral licks/oases) of Western Siberia: Shestakovo-Kochegur (25.9–17.8 ka BP) in the Kemerovo region, Volchia Griva (17.8–11 ka BP) in the Novosibirsk region and Lugovskoye (16.5–10 ka BP) nearby Khanty-Mansiysk. Additional sites studies included sites (30–10 ka BP) from other regions of Northern Eurasia also with mass mammoth remains (Gari, Berelyokh, Krasnoyarskaya Kurya, Kraków Spadzista Street, P?edmostí, Dolní Věstonice, Milovice and others). The results suggest that just at the end of the Pleistocene, large herbivorous mammals experienced a powerful geochemical stress which would manifest as mass destructive changes of bones due to enzootic diseases caused by mineral deficiency. Remains characterized by destructive changes are common and prevalent in all collections. Maximum damage was discovered in the bones and teeth of Mammuthus primigenius Blum. The most typical signs of osteodystrophy were osteoporosis, osteofibrosis, osteomalacia, osteolysis, cartilage atrophy, exostoses and fractures, resulting in the formation of false joints, ulcers and friction grooves on articular surfaces. The results of the paleoecological analysis suggest that the larger part of Northern Eurasia at the end of Pleistocene was extremely unfavourable for the existence of megafauna. The disruption of the abiotic relationships caused by the cardinal transformation of geochemical landscapes could have become the main reason for the wide-spread enzootia and, finally, the extinction of the mammoth.  相似文献   

11.
Non‐contact optical 3D‐profiling instruments are often used in the study of surface modifications on fossil mammalian bone. The advantage of optical laser scanning for the study of fossil and sub‐fossil bone is its non‐contact nature, allowing the investigation of fragile and poorly preserved surfaces. The high resolution and fast measuring rate of this method make it an alternative to scanning electron microscopy (SEM) investigation if topography is to be visualized. This study analyses clusters of incisions in a suid humeral fragment from the Pliocene Upper Laetolil Beds. The marks show a characteristic crest structure that is also frequently found in mandible marks produced by the Australian termite species Mastotermes darwiniensis. The marks from the Laetolil Beds are, therefore, interpreted as also being caused by insect mandible action. An as yet unknown large insect species capable of modifying bone with their mandibles is thus postulated in the palaeohabitat represented by the hominid‐bearing Upper Laetolil Beds. Copyright © 2001 John Wiley & Sons, Ltd.  相似文献   

12.
Is it possible to determine low‐temperature cooking in archaeological bones? The indirect exposure of bones to fire at low temperature (≤ 100 °C), linked to cooking, produces macroscopic modifications on these bones. These modifications have not been clearly or systematically described previously. Instead, physicochemical changes at nanometric level are only now beginning to be understood. In this paper, our principle aim is to explore new methods and techniques that correlate macroscopic features such as smoothness or light transparency with physicochemical characterization results that could aid towards detecting cooked bones in the archaeological record. This study then selected 11 archaeological samples, both human and non‐human. Bones were considered to be thermally treated or not, on the basis of macroscopic criteria. Complementary characterization techniques were used to study morphology (scanning electron microscopy and small angle X‐ray scattering), structure (X‐ray diffraction and transmission electron microscopy), local composition (energy‐dispersive X‐ray spectroscopy) and texture (gas adsorption). Indeed, fractal dimension, particle size, crystalline percentage or specific surface area may well explain some of the macroscopically observed modifications on these samples. The possibility that such apparent modifications may also be due to diagenesis is also considered. From an archaeological point of view, the results are promising. Our characterization of human and non‐human bones demonstrates that physicochemical techniques are complementary and provide good criteria against which to distinguish boiled from un‐boiled archaeological samples. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   

13.
A small pit in the articular surfaces of the third tarsometatarsal joint has been noted with particularly high frequency in North American Indians. This pit varies in depth, and covers most of the inferior third of the articular surfaces of the third metatarsal and the lateral cuneiform; it is accompanied by remodelling of the inferior surfaces of the bones involved. In the present study, patterns of occurrence are examined in a prehistoric skeletal population from west-central Illinois. This population is extremely well preserved, enabling a thorough examination of feet as well as hands for most individuals. The sample included 496 adults and juveniles above the age of 6 years. Of this total population, 18 per cent exhibit the variation, which occurs more frequently in females and is unrelated to size. Furthermore, 29 per cent of the individuals in which it occurs exhibit this variant only unilaterally, with no significant side differences. Various lesions, trauma and acquired or activity-related aetiologies are explored, as are the patterns of sex association, occurrence near an area of ligamentous attachment and lack of age and size association. It is hypothesized that a discrete genetic trait is represented in the third tarsometatarsal joint of this population in the form of an anomalous interosseous plantar ligament. © 1997 by John Wiley & Sons, Ltd. Int. J. Osteoarchaeol., 7 : 124–132 (1997) No. of Figures: 3. No. of Tables: 2. No. of References: 26.  相似文献   

14.
The relationship between cranial deformation and the occurrence of extra‐sutural bones remains poorly understood. Scholars are divided about whether or not cranial deformation causes an increased occurrence of these bones, and even those who agree that deformation does have an influence often disagree about which locations on the crania are most impacted. Part of this issue clearly stems from the difficulties in finding appropriate samples from which to test the hypothesis that deformation leads to an increased expression of extra‐sutural bones. The present study examines the effects of fronto‐occipital and occipital‐only deformation on the occurrence of extra‐sutural bones through an analysis of 59 deformed and undeformed crania from the Philippines. Relative to the undeformed crania, both deformed samples showed an elevated number of extra‐sutural bones. Using two different statistical tests, we identified a significantly higher occurrence of extra‐sutural bones at two distinct cranial localities for both the fronto‐occipitally deformed crania (coronal suture and asterion) and for those showing only occipital flattening when compared to the undeformed crania (lambdoidal and asterion). However, as our data reveal, individuals with highly elevated occurrences of extra‐sutural bones are not necessarily deformed. As such, we argue that deformation practices may have a positive impact on the formation of extra‐sutural bones; however, future studies using larger samples of deformed and undeformed crania—ideally from the same site—will be necessary to distinguish between the influence of cranial deformation on extra‐sutural bone formation relative to other population factors which may play a role in shaping variation in this feature. Copyright © 2010 John Wiley & Sons, Ltd.  相似文献   

15.
Abstract

The spectacular relief of the sandstone inselbergs is maintained by an interplay of geological structure and weathering/erosion processes, in that vertical joints and faults provide the foci along which most weathering and erosion take place. There are three major varieties of sandstone breakdown; the first is failure of large rock masses along vertical joints, leading to rockfall. Associated with this process is the mechanical breaking of falling blocks upon impact, in some cases right down to the origjnal sand grains. Rockfall maintains vertical or steep slopes, provided basal talus is removed. The second variety is liberation of small blocks by weathering along closely-spaced joints and bedding planes. Rock prone to this style of erosion tends to be less steep and may have basal slopes buried by rubble. The third variety is grain by grain weathering by solution of cement. This process is the most fundamental, as it not only wears away the surfaces but attacks joints, leading to the processes described above. Grain by grain weathering is slowed or prevented on some surfaces by development of oxide rinds, particularly where run-off is concentrated.

These processes result in deposition of debris at slope bases, but in most cases the debris is quickly reduced to sand and removed by wind and water. Relatively clean slope bases allow slopes to retreat parallel to themselves. Where debris collects faster than it is reduced to sana, slope angles tend to decline until they reach the angle of repose of the debris.

Differences in structural expression of the various lithological units result in differing erosional characteristics. The Saleb Formation is typified by relatively gentle slopes littered with debris, due to thinly spaced joints. The Ishrin Formation, witll widely spaced vertical joints, is typified by rockfall of large masses. It is the major cliff-former. Grain by grain weathering, influenced by variations in varnish development, has produced spectacular tafoni on some Ishrin cliffs. The Disi Formation is extremely friable and although slopes are relatively gentle they are mostly rubble free. The Disi in many places forms rounded domelike shapes which may be due to exfoliation along pressure-relief joints. The Um Sahm Formation is highly fractured and similar in appearance to the Saleb.

Igneous rocks, where exposed below the sandstones, are undergoing chemical weathering, particularly along joints. The results are tors, tafoni, and large amounts of grüss.

The desert floor between inselbergs is in some places a bare bedrock surface with an integrated drainage network, and in other places a sand or playa surface. Running water seems to have been a major agent in shaping the floor, but is less important now than in the past. Transportation of sand by wind is common but there is no evidence for significant eolian aggradation or degradation at the present time.

A minimum rate of surface retreat by grain by grain weathering is 5 cm./1,000 years, based on weathering ofNabataean ruins. Overall slope retreat should be significantly greater, due to added effects of rockfall and removal of blocks by running water.  相似文献   

16.
Abstract

Anasazi pit structures dating to the Basketmaker III and Pueblo I periods (ca. A.C. 500 to 900) in the Four Corners region of the American Southwest experienced a variety of different processes at abandonment, ranging from dismantling the superstructure to intentional burning. Data from 88 pit structures are used to examine the relationship between these processes and the causes of pit structure abandonment. Results suggest that burning was not usually the result of catastrophic events, such as accident or warfare, but may be part of ritual activities or even a response to insect infestation. The incidence of burning does not seem to increase over time as a result of the postulated transition of pit structures from domestic to ceremonial uses. Dismantled and trash-filled pit structures suggest that new dwellings were often constructed near abandoned ones, perhaps because the old structure was deteriorating. A few pit structures with human bodies on the floor at the time of abandonment may signal the desertion of the entire settlement.  相似文献   

17.
The taphonomy of invertebrates from 16th‐century cesspits at St Saviourgate, York, was investigated. Earthworms, fly larvae and puparia are preserved through replication in calcium phosphate, a process facilitated by acidic cesspit pore water and by the presence of abundant organic matter, bones and shells. Features preserved by mineralization include muscles, blood vessels and setae. Non‐mineralized invertebrate remains include puparia and beetles. Py–GC/MS (flash pyrolysis–gas chromatography/mass spectrometry) revealed a very high level of preservation of structural biomolecules, with all the protein and chitin markers that are evident in the living forms still being detectable in the divalent remains.  相似文献   

18.
The burials of famous Xiongnu people are a unique source of information about Xiongnu culture, due to the variety of organic findings. SRXRF analysis of hair, clay, bones, teeth and woollen cloth was carried out. An anomalously high copper content was observed in all hair samples, whereas the levels of copper in bone and clay were low. To define the hair morphology and the elemental distribution in the hair cross‐section, high‐resolution X‐ray computed tomography (HRXCT) and energy‐dispersive spectroscopy (EDS) with scanning electron microscopy (SEM) were used. The X‐ray absorption fine‐structure method (XAFS) was applied to determine the local copper environment. The majority of the copper species in the hair and enamel samples are present as Cu2+ cations in a distorted octahedral (4 + 2) coordination, surrounded by light ligands (oxygen/nitrogen). A similar distorted octahedral coordination is typical for both inorganic mixed oxide/hydroxide Cu nanosystems and metal–organic Cu complexes (with oxygen/nitrogen).  相似文献   

19.
20.
We present a reconstruction of the three‐dimensional (3D) geometry and gold grade distribution of shear zone‐hosted, Au‐mineralized, quartz–tourmaline veins of the Sigma deposit (Abitibi belt). Host shears and veins form a network of anastomosing, steeply dipping structures associated with smaller subhorizontal extensional veins. Our reconstruction has been carried out using the exceptionally large geological database of the mine. From this database, we extracted the geometric position, thickness and gold grades of geometrically best‐defined steep veins contained in a representative subvolume of the deposit. These data allowed the 3D representation of 53 veins, which have been constructed by fitting surfaces through the geometrical data and by contouring thickness and gold grade. The geometry of the network is mainly characterized by: (i) a few large segmented veins, with sinuous and helicoidal shape, and typical vertical dimension of >100 m; (ii) a large number of smaller vertical veins, some of which splay off the steep veins with high dip angles; (iii) subhorizontal extension veins (joints) located at, or close to, the tips of steep veins. The absolute thickness of the vertically short veins is the same as that of the large veins, suggesting that they formed simultaneously, but only a few of them interconnect to form vertically continuous bodies. Patchy, vertically elongated zones of high dilation are present in the large veins, and are poorly correlated with Au‐rich zones. They presumably represent former high‐permeability zones of the network. The highest gold grades occur at the interconnections between the large veins and small splays or subhorizontal joints. This indicates the important role of vein interconnection for fluid flow and gold precipitation within the network. Combining the calculation of the volume of the network with the estimation of tourmaline abundance in the veins, we calculate that 2.1 × 106 m3 of tourmaline and 3.2 × 106 m3 of quartz precipitated during Au deposition.  相似文献   

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