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Methodological advancements in geoarchaeology and spatial and chronological modeling are opening new avenues to interpreting large coastal shell-bearing sites. We document the developmental histories of two such sites around Prince Rupert Harbour, Canada, using systematic percussion coring, intensive radiocarbon dating, and 3D surface mapping with Total Station and LiDAR. We also re-analyze a third site (Boardwalk/GbTo-31) excavated and radiocarbon dated in the 1960s, 1970s, and early 2000s using archival field notes, site maps, and stratigraphic profiles georectified using LiDAR. We map the natural landform beneath the sites and document the degree to which people physically modified landforms through the deposition of massive shell accumulations. We model site development through time and space and use accumulation rates and OxCal modeling to test for intentional deposition events. All three sites demonstrate complex and heterogeneous occupation histories. At each we identify instances of very rapid deposition that effectively terraced and extended parts of the natural landform to create places for constructing houses, though these episodes take place within longer histories of slower quotidian deposition. The anthropogenic modifications to the coastline in this area are the result of these mixed processes associated with long histories of occupation.  相似文献   
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This study compared bone collagen extraction techniques that included treatment with sodium hydroxide and 30 kDa ultrafilters using a set of well‐preserved, humic‐contaminated archaeological marine mammal bones. Treatment with sodium hydroxide was effective at removing humic contaminants from archaeological bone, although yields were significantly decreased. Yields were also significantly decreased by ultrafiltration although this study produced no evidence that 30 kDa ultrafilters were effective at selectively removing humic contaminants from archaeological bone. The combination of sodium hydroxide treatment and ultrafiltration did not produce superior results to the treatment involving only sodium hydroxide. Archaeological samples exhibiting darker colouration indicative of humic contamination should be treated with sodium hydroxide to remove these contaminants. Copyright © 2017 John Wiley & Sons, Ltd.  相似文献   
4.
Metals present in the environment (soil, water and atmosphere) can affect food safety and human health through bio‐accumulation and bio‐magnification phenomena. Human exposure to the metals may take place through the environment and by ingesting contaminated food (including water), determining harmful effects usually detectable over the long term. Starting with the Industrial Revolution, local occurrence and concentration of metallic contaminants in the environment have been exponentially increasing: it has been assessed that, nowadays, daily absorption of lead, by North American people, is noticeably greater than that during prehistoric times. In this study, we measured concentrations of cadmium, lead and zinc in 153 bone samples (femurs) of Iron Age inhabitants of Central Italy (Abruzzo): the Samnites from the Alfedena Necropolis (2600–2400 bp ). The data found are in agreement with the results of similar published studies. Heavy metal concentrations varied widely among samples with the exception of zinc. A significant difference (p same Mann–Whitney test <0.05) in cadmium bone levels was found between male (0.08–1.8 mg/kg, median 0.31 mg/kg) and female samples (0.05–1.3 mg/kg, median 0.53 mg/kg). Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   
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This paper presents evidence for severe lead contamination among children of samurai families living in a castle town in Edo period Japan (1603–1867). Excavated rib bones were analyzed by atomic absorption, and soft X-ray roentgenograms of long bones were taken. The median values of lead concentration in the bones of children 3 years of age and under(1241.0 μg Pb/g dry bone) and 4–6 years of age (462.5 μg Pb/g dry bone) were significantly higher than those of adult males (14.3 μg Pb/g dry bone) and females (23.6 μg Pb/g dry bone) (p < 0.001). In addition, that of children over 6 years of age (313.0 μg Pb/g dry bone) was significantly higher than those of adult males (p < 0.01) and adult females (p < 0.05). The median value of lead in the bones of children 3 years of age and under was over fifty times higher than that of their mothers (adult females). Hypertrophy was seen in the long bones of five samurai children. In this area, lead lines or lead bands were distinguished by soft X-ray roentgenogram. Samurai children suffered from severe lead contamination in Edo period Japan. When the mothers were nursing their children, the children might have ingested their mother’s white lead non-selectively.  相似文献   
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As the only type of instrument capable of determining artifact geochemistry in a wide variety of settings, portable X-Ray Fluorescence (PXRF) may be frequently utilized as probably the best option for collecting data when removal of objects in part or in whole is unfeasible. However, using PXRF in circumstances where sample selection and preparation diverge from standards developed for lab-based instrumentation requires assessing the impact of new and potentially limiting factors to establish the validity of the method in these new contexts. Here we examine the effects of surface contamination and chemical weathering on the ability to assess provenance of igneous building stones used in the Cuzco region of Peru. Surface contamination was assessed through comparing low-impact cleaning methods on diorite and andesite blocks, and weathering was examined by comparing weathered vs. fresh surfaces of samples from two andesite quarries. In general, the lightest elements were most impacted by contamination and weathering while measurements of many of the heavier elements commonly used in provenance studies were relatively unaffected. Concentrations of Pb and Zn were problematic in the urban context of Cuzco because of pollution. Ability to determine provenance of building stones within those limitations (i.e., the validity of this application of PXRF) was demonstrated in a preliminary study by comparing measurements from uncleaned, exposed building stones in the region to fresh quarry samples.  相似文献   
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This study uses quartz-based optically stimulated luminescence dating to determine when a massive fortification wall (W11186) was constructed in the archaeological site of Tall Zarʿa in the Jordan Valley. A total of 11 samples of sediments were taken from a trench on the north side of the wall (extramuros). The extracted quartz grains had good luminescence characteristics and were identified as well bleached by comparison with feldspar infrared-stimulated luminescence (IRSL) ages. The optical ages showed that the deposition against the wall occurred in two different periods. The first was around 3.20 ± 0.07 ka ago (Iron Age), and the second was around 2.28 ± 0.08 ka (Hellenistic period). Human activity was evident because of the intermixing of cultural material with the presumed naturally deposited units.  相似文献   
8.
Residents living in close proximity to contaminated sites may experience adverse effects from financial losses and property devaluation, leading to poor mental health and physical illnesses—effects that may require compensation. The most common legal process of seeking compensation is the toxic tort—litigation pressed on the basis that contamination has harmed the victims. Several recent toxic tort class actions in Australia brought by residents living in areas affected by contamination from per- and poly-fluoroalkyl substances (PFAS) exemplify that process. Two such actions, those at Williamtown and Richmond, provide an opportunity to explore how toxic torts currently function as a means to secure compensation, whether they mitigate the harms of the contamination and considering how spatio-legal manoeuvres may shape the litigation. In this article, we use a legal geography approach to analyse how plaintiffs’ bodies, litigants’ properties, and the state are constructed and represented by parties involved in these toxic torts. Legal geographers contend that examining the spatio-legal manoeuvres made via litigation can make visible the effects of legal action on those involved and draw out how the law and its instruments may shape places and communities. Toxic tort class actions have allowed those affected by the contamination to be heard and receive some compensation. However, we argue that they do little to alleviate plaintiffs’ concerns about the effects of contamination on their health, properties, and the environment. The findings have significance given that torts will likely play an increasingly prominent role in dealing with such challenges.  相似文献   
9.
From long-term stratigraphic records in Pacific Island archaeological sites, researchers have documented alterations to molluskan species richness and abundance, decreases or increases in mollusk shell size and, in rare cases, human foraging may have contributed to the extirpation of mollusk taxa. Mollusks perform critical ecosystem functions in tropical intertidal environments, including improving water quality through filtration, regulating algal cover, and increasing habitat and substratum complexity through ecosystem engineering. These critical ecosystem functions can be negatively affected by human foraging, possibly contributing to decreased resilience of coral reefs to climatic alterations. We review modern ecological research on human impacts to mollusks and intertidal ecosystems that illustrates the mechanisms and effects of human foraging. We then examine centuries to millennial scale archaeological records from the Pacific Islands to understand long-term, time-averaged trends in human impacts to intertidal ecosystems.  相似文献   
10.
A principal problem facing human DNA studies that use old and degraded remains is contamination from other sources of human DNA. In this study we have attempted to contaminate deliberately bones and teeth sampled from a medieval collection excavated in Trondheim, Norway, in order to investigate this poorly understood phenomenon. Five pairs of teeth and bone samples were bathed in water containing various concentrations (from 10−9 and 10−21 g/l) of purified ΦX174 DNA. Subsequently the samples were subjected to a routine decontamination protocol involving a bleach bath followed by exposure to λ=254 nm ultraviolet light, prior to DNA extraction and analysis for evidence of the persistence of the contaminant. The results support previous speculation that bone is more susceptible to water‐borne sources of contaminant DNA, although both bone and teeth are readily contaminated and are difficult to decontaminate using the tested protocol. We believe that this is largely due to the porous nature of bone and teeth facilitating the deep penetration of the contaminant DNA. To simulate a more realistic handling situation, 27 further teeth were directly handled and washed, then decontaminated, prior to assaying for the residual presence of the handler's DNA. Surprisingly, although our results suggest that a large proportion of the teeth were contaminated with multiple sources of human DNA prior to our investigation, we were unable to contaminate the samples with further human DNA. One potential explanation may be the deposition of sediment or other structural changes that occur within the samples as they desiccate post‐excavation, which may protect samples from subsequent contamination, but also prevent the efficacy of bleach baths in decontaminating specimens. Copyright © 2006 John Wiley & Sons, Ltd.  相似文献   
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