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1.
We have investigated change in subsistence during the transition to agriculture in the site of Jiahu, Henan Province, China, using stable isotopic analysis of collagen and apatite in human bones. Millet agriculture is well documented at drier high latitudes of the Yellow River Valley, while rice agriculture predominated at wetter lower latitudes of the Yangtze Valley region. The early Neolithic site of Jiahu lies near the boundary between the drier north and wetter south. Archaeobotanical evidence shows that rice was a significant component of diet at Jiahu, but its δ13C value is similar to that of other foods, and therefore cannot be conclusively identified by carbon isotope analysis. Foxtail and broomcorn millets are the only C4 crops known for the Chinese Neolithic. Because of their high δ13C values, their consumption can be evaluated by stable carbon isotope analysis of human bone. Collagen reflects mainly the δ13C value of dietary protein, and apatite accurately records that of the whole diet. Isotopic analysis of 15 well-preserved samples from three periods shows that collagen δ13C values were very low for almost all individuals, suggesting C3-based foods dominated their diets. However, apatite carbonate δ13C values and δ13C spacing between collagen and apatite (Δ13Cap-co) indicate that millet may have been a minor component of the diet in this region. Individuals, who consumed the smallest amounts of animal protein, as indicated by low δ15N, generally had the highest apatite δ13C values. Archaeobotanical evidence for millet at Jiahu is needed to support this interpretation.  相似文献   

2.
This study compares trends in dietary composition in two large cemetery populations from the site of Kulubnarti (AD 550–800) in Sudanese Nubia. Bone collagen and bone apatite carbonate were analysed to characterise stable carbon, nitrogen and oxygen isotopes. Previous research on these cemeteries has suggested marked differences in nutritional status and health between the populations. Contrary to expectations, there were no significant relationships between any isotopic indicators related to sex or cemetery of burial, suggesting no isotopically‐measurable differences in diet. However, collagen δ13C and δ15N were significantly related to age, suggesting age‐related differences in protein intake or other factors. Weaning trends are gradual and variable, with the range in δ15N values exceeding 4‰ among infants/young children (0–3 yrs) and standard deviations exceeding 1‰ in collagen δ13C and δ15N for both infants/young children and subadults (4–17 yrs). This suggests varied weaning strategies among both populations and variable diets prior to adulthood. Also observed was a distinct range of isotopic carbon and nitrogen values among individuals classified as subadults (4–17 yrs), who are depleted in collagen δ13C and δ15N relative to adults. However, both infants/young children and subadults are slightly enriched in δ18O relative to adults, which suggests the presence of non‐local individuals or age‐related variation in water sources. While most isotopic studies of age‐related dietary trends have focused on reconstructing the weaning process, this study presents findings that indicate tripartite isotopic trends distinguishing infancy, subadulthood and adulthood as separate dietary categories. Broad similarities are evident between the results presented here and those from several earlier studies of smaller populations and to nutritional studies of modern communities. These findings suggest that further research into health disparities at Kulubnarti should focus on non‐dietary causal factors, and more generally, that greater attention should be paid to subadulthood in palaeodiet studies. Copyright © 2006 John Wiley & Sons, Ltd.  相似文献   

3.
In this pilot study, stable carbon and nitrogen isotopes from bone collagen and apatite of skeletons from the 11th and 12th century cemetery in Giecz, Poland are interpreted. Isotope values from a small number of fish and animal bones from the same archaeological site are also examined. The goal of this research is to provide preliminary evidence of diet for a group of medieval Polish peasants, with particular emphasis on sex-based differences in diet. Results of isotope analyses suggest diet of this early medieval population was omnivorous and terrestrial-based. Fish bones sampled exhibit low δ13C ratios, and in half of the cases are significantly enriched in 15N, indicating they are freshwater species. Human bones do not reflect these signatures, suggesting freshwater fish were not a significant source of dietary protein at Giecz. The 13Ccoll from some human bones is enriched beyond what might be expected from an exclusively C3 diet. Associated mammal bones do not exhibit similarly elevated δ13Ccoll ratios, suggesting enrichment among humans is not due to consumption of animals foddered on C4 plants. Two possible sources of 13Ccoll enrichment are marine fish in diet and direct consumption of a C4 plant, such as millet. The δ13C values obtained from bone apatite of a small subset of humans suggest that millet contributes to 13Ccoll enrichment, although at least three individuals may have also consumed small amounts of marine fish. Sex-based differences in δ15N ratios indicate that men consumed relatively more animal products (meat or dairy) than did women. There is also a correlation between δ13Ccoll and δ15N values in skeletons of men that is absent in women. These carbon and nitrogen isotope data are the first reported for any Polish population and contribute to a more complete picture of dietary adaptation and social organization in medieval Europe.  相似文献   

4.
In bone, the spacing between δ13C in collagen and bioapatite carbonate is greater in herbivores than carnivores, with implications for understanding animal dietary ecology from surviving hard tissues. Two explanations have been proposed: varying diet composition or differences in physiology between herbivores and carnivores. We measured the isotopic effects of carnivorous and herbivorous diets on a single species, to test the effect of diet composition alone. Protein δ13C and δ15N and carbonate δ13C were measured on egg and bone from hens on different diets. Herbivorous hens had a +14.3‰ spacing between egg albumen and shell δ13C, compared to +12.4‰ for omnivorous hens, and +11.5‰ for carnivorous hens. The bioapatite–collagen Δ13C spacing was measured as +6.2‰ for herbivorous hens, and calculated as +4.3‰ for omnivorous hens, and +3.4‰ for carnivorous hens—similar to observed mammalian herbivore and carnivore bioapatite–collagen Δ13C differences. We conclude that a shift in diet composition from herbivory to carnivory in a single species does alter the bioapatite–collagen carbon isotopic spacing. Our data strongly suggest that this results from differences in the Δ13Cbioapatite–diet spacing, and not that of Δ13Ccollagen–diet.  相似文献   

5.
The carbon (δ13C) and nitrogen (δ15N) isotope ratios of human bone collagen have been used extensively over the last 40 years to investigate the diet of past populations. It has become apparent that bone collagen can give an unreliable temporal dietary signature especially in juveniles. With higher temporal resolution sampling of collagen from tooth dentine, it is possible to identify short-term changes in diet previously invisible in bone. This paper discusses the inherent problems of using bone collagen for dietary studies and suggests better sample choices, which can make our interpretations more robust, using breastfeeding and weaning as an example.  相似文献   

6.
Here we report δ13C and δ15N measurements of serial sections of human deciduous and permanent tooth dentine from archaeological samples taken from the medieval village site of Wharram Percy, Yorkshire, UK. We found a pattern of enrichment, for both δ13C and δ15N, where the tooth crown was greater than the cervical part of the root, which in turn was greater than the apical portion of the root and the associated rib collagen values. This pattern reflects a decrease in the consumption of isotopically enriched breast milk and the introduction of less enriched weaning foods in the diet. The (mean±SD) difference between the deciduous second molar crowns and corresponding rib samples from the same individuals after 2 years of age was 1.2±0.4‰ for δ13C and 3.2±0.8‰ for δ15N. The δ15N values are as predicted, but as there were no C4plants at Wharram Percy, this 1.2‰ enrichment in δ13C represents clear evidence of a carbon trophic level effect in collagen from breastfeeding infants. Carbon and nitrogen results also show that the infant diet among those who died in infancy did not differ from those who survived into childhood. This study demonstrates the promise of using dentine serial sections to study the temporal relationships of breastfeeding, weaning, and dietary patterns of single individuals.  相似文献   

7.
During the late Longshan period (ca. 4200–3900 BP) settlements on the Central Plains of China underwent a diversification in food production technologies, which set the stage for rapid economic and social development. The introduction of novel domesticates such as rice, wheat, cattle, and sheep not only provided more food choices, but also changed ideas concerning land use, farming techniques, and the use and mobilization of large scale labor forces. To better understand the contribution that these new dietary items and practices made to shaping the late Longshan period societies, a stable isotope ratio study of humans (n = 12) and animals (n = 42) was conducted at the late Longshan period site of Wadian. The human δ13C and δ15N values are clustered into two distinct groups. One group of nine individuals (δ13C = −9.9 ± 0.7‰; δ15N = 7.5 ± 0.5‰) had a predominately C4 diet based on millet grains with little protein input from the domestic animals. The other group of three individuals (δ13C = −14.3 ± 0.8‰; δ15N = 10.2 ± 0.3‰) had a mixed C3/C4 diet of millets and rice and were consuming sheep and cattle. The animals also displayed dietary diversity with the pigs (δ13C = −11.3 ± 2.5‰; δ15N = 6.9 ± 1.0‰, n = 10) and dogs (δ13C = −10.1 ± 1.0‰; δ15N = 7.2 ± 1.1‰, n = 7) having mostly a C4 plant based diet (millets). In contrast, the cattle (δ13C = −12.8 ± 2.1‰; δ15N = 7.6 ± 0.7‰, n = 9), sheep (δ13C = −16.7 ± 0.9‰; δ15N = 7.6 ± 0.1‰, n = 2), and cervids (δ13C = −20.8 ± 0.9‰; δ15N = 5.0 ± 1.2‰, n = 10) had diets with a greater contribution from C3 sources such as rice and wild plants. The discovery that humans and animals had different subsistence patterns indicates dietary complexity at Wadian and that rice agriculture, and cattle and sheep husbandry practices were already an important part of the local economy by the late Longshan period in the southern region of the Central Plains of China. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   

8.
Human osteological samples (n = 23) taken from different anatomical parts of 11 individuals from the early modern (16th–18th century AD) site of Roccapelago (Modena, Italy) were systematically analysed for δ13C, δ15N and trace elements to investigate their diet. δ13C and δ15N correlate and show a high variability between individuals, attesting to the dietary contribution of C4 plants. This is supported by pollen analysis of the burial site samples, which revealed the presence of maize. δ15N correlates with Sr/Ca, suggesting that the main protein source could have been milk and dairy. We therefore interpret the strong correlation between δ13C and δ15N as evidence for C4‐plant foraging practice and the exploitation of livestock for meat and milk, combined with possible direct intake of C4 plants. The Roccapelago site represents an important case study to track the evolution of the post‐medieval diet and the introduction of maize cultivation in southern Europe, as also attested by historical sources.  相似文献   

9.
Isotopic assessment of bone collagen is often used as an environmental tracer in both contemporary and palaeoenvironmental studies. However, variability in the isotopic composition of this tissue remains poorly understood for naturally occurring and wild populations of animals. In this study the stable carbon isotope composition of both diet and bone collagen was assessed for a population of red kangaroos (Macropus rufus). Animals sampled ranged in age from approximately 10 months to 15 years. The diet of this population, estimated from faeces collected in the field, varied from predominantly C4grasses in late summer (δ13C⋍−16·5‰) to mostly C3herbage in late winter (δ13C⋍−22·5‰), with a long-term average δ13C of between −19 and −20‰. Bone collagen was enriched in13C by 3 to 4‰ in older animals relative to pouch young. Isotopic analysis of hair, used to assess more recent diet in individuals, indicated that diet selection was similar in all animals that had been weaned. We suggest that the most likely explanation for the age-dependent relationship in the δ13C of bone collagen occurs because milk (the only source of nutrition in suckling kangaroos) is not fractionated in the same manner as plant-derived carbon during its assimilation into skeletal tissue. If this is the case, then such a relationship should be most predominant in mammals that have low birth weights (relative to the adult mother) and gain significant weight from milk. Whatever the precise mechanism(s) for the observed fractionation, bone collagen of kangaroos seems to retain an isotopic memory of the carbon laid down prior to weaning, which takes several years to be diluted and replaced with carbon derived from an “adult” herbaceous diet. These results have implications for palaeoecological research where fossil skeletal tissue is used as dietary or environmental tracers particularly if the relative age of the animals sampled is unknown.  相似文献   

10.
This study investigates human dietary patterns and economic trends at the coastal site of Ancón, Peru during the Andean Middle Horizon (550AD –1000AD ) using stable isotopic data from 32 individuals buried at the site. δ13C and δ15N results from human bone collagen and δ13C from human tooth enamel and bone carbonate indicate that inhabitants consumed a mixed diet composed primarily of marine protein and C4 resources, with only marginal reliance on C3 foods. Over time, Ancóneros appear to have relied more heavily on C4 resources, particularly maize, despite the fact that the crop could not have been grown locally. These results are notable given that C3 rather than C4 or marine foods dominate the site's archaeological record. These data suggest that Ancón's inhabitants either had access to more fertile land up‐valley where maize could be cultivated successfully or that they engaged in trade relationships with their valley neighbours. A third possibility is that increased maize consumption at Ancón during the Middle Horizon resulted from Wari imperial influence and interregional exchange. Comparisons of δ13C values in enamel and bone carbonate from Ancón individuals indicate that δ13Ccarb_enamel values are significantly more positive than δ13Ccarb_bone values. This suggests that the diets of young children were systematically enriched in 13C compared to that of adults, perhaps as a result of nursing activity and/or differential dietary practices among various age groups at the site. Copyright © 2009 John Wiley & Sons, Ltd.  相似文献   

11.
Stable isotope analyses have been applied to human and faunal bone collagen from the Varna I and Durankulak cemeteries to explore palaeodietary adaptations in the Neolithic and Eneolithic (Copper Age). The results suggest both populations primarily utilised terrestrial, C3-based diets, despite their proximity to the Black Sea. The wider δ15N range of the Durankulak humans likely indicates the differential utilisation of terrestrial meat sources, which is probably related to the degree to which primary and/or secondary ovicaprid products were consumed, particularly since ovicaprid δ15N values differ from other herbivores. The isotopic distribution of Varna I reflects a linear relationship between δ15N and δ13C, suggesting that a minority of individuals enriched in both isotopic parameters supplemented their diets with marine resources. These burials include the well known ‘chieftain’ (burial 43) and show notable material wealth by way of grave goods. At the population level, however, there is no significant correlation between stable isotope values and material wealth at Varna I, a fact with implications for theories regarding emergent social/economic hierarchies in Balkan prehistory. Five burials at Durankulak were found to have relatively enriched δ13C and δ15N values with respect to the rest of the population. These burials reflect a prominently marine-based or mixed terrestrial C3-based diet that included C4 inputs, possibly from millet, for which the limitations of stable isotope analysis on bulk collagen are not able to differentiate. AMS dating has shown that these burials belong to a much later period.  相似文献   

12.
Here we report the bone collagen carbon and nitrogen isotopic results of humans (n = 33) and animals (n = 58) to reconstruct the dietary practices of an early Qin population dating to the Zhou Dynasty (Late Western–Early Eastern period ca. 700–400 BC ) at the Xishan site in Gansu Province, China. The humans have a very large range of δ13C (−23.3‰ to −7.1‰) and δ15N (4.3‰ to 10.9‰) values which reflects extraordinarily diverse diets and included individuals with predominately C3 as well as those with exclusive C4 diets. This wide span of isotopic results produced a subtle linear trend (R2 = 0.62) in the human data, which paralleled the animals across the C3 and C4 environmental gradient. However, the majority of the individuals had a predominately C4 diet based on millet with δ15N results only slightly elevated above the animals, except for the pigs and cattle. This is evidence that many of the animals were likely used for their secondary products, labour or as sacrificial offerings and that pork and beef were the main sources of animal protein for the population. High status individuals had elevated δ15N values (10.2 ± 0.6‰) compared to medium (8.9 ± 0.3‰) and lower status (8.8 ± 0.8‰) individuals, possibly related to increased animal protein in the diet. Differences related to gender were also found with females having elevated δ13C (−11.2 ± 1.9‰) and δ15N (9.4 ± 0.8‰) values compared to the males (δ13C = −14.1 ± 4.2‰; δ15N = 7.9 ± 1.9‰), but these results necessitate caution given the large number of individuals that could not be sexed. The results of this study support the view that the early Qin people were a more sedentary society focused on millet agriculture and animal husbandry, and that they were influenced by the pre‐existing populations of the central Gansu region. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   

13.
Stable carbon and nitrogen isotope ratios from bone collagen in skeletons from the Byzantine (5th–7th century AD) monastery of St. Stephen’s in Jerusalem were examined in conjunction with a review of historical sources detailing dietary practices during this period in the Levant. Relatively low δ13C ratios (−19.0 ± 0.5‰, 1σ) indicate a diet consisting primarily of C3 sources and display continuity with textual records describing monastic daily life. Conversely, human δ15N values (9.6 ± 1.2‰, 1σ) are enriched in 15N relative to local fauna (7.3 ± 1.1‰, 1σ) and point to the contribution of animal protein to the diet, an unexpected result based on both the rarity and expense of these luxury food items as well as dietary prohibitions associated with an ascetic monastic lifestyle. No sex-based differences in diet were detected for either δ13C or δ15N values, suggesting that men and women consumed isotopically similar foods. As the vast majority of monastic communities in the ancient Near East were located in the desert, the urban setting of St. Stephen’s monastery allows for a unique glimpse into a rarely-explored facet of Byzantine life.  相似文献   

14.
Spacing between stable isotope values in bones and teeth is a valuable tool for examining dietary influences and diagenesis. This study examines carbon and oxygen isotope values from collagen and hydroxyapatite (structural carbonate and phosphate) in archaeological human bones and teeth to derive species‐specific correlation equations and isotope spacing values. The δ13Ccollagen and δ13Cstructural carbonate in bone and dentin collagen show a strong correlation (R = 0.87, 0.90, respectively) with an average Δ13Ccarb‐coll spacing of 5.4‰. The consistency of this isotope spacing with other large mammals and in humans with both low and high protein intake (as indicated by enriched δ15N values) suggests a similar allocation of protein‐derived carbon and whole diet‐derived carbon to collagen and structural carbonates, respectively, as other terrestrial mammals regardless of absolute meat intake. The δ18Ostructural carbonate and δ18Ophosphate show the strongest correlation in enamel (R = 0.65), weaker correlations in dentin (R = 0.59) and bone (R = 0.35), with an average Δ18Ocarb‐phos of 7.8‰. This isotope spacing is slightly lower than previously reported for large mammals and limited available data for humans. The results potentially indicate species‐specific fractionations and differing access to body water and blood‐dissolved inorganic carbonates in the presence of collagen formation. The use of correlation between δ18Ostructural carbonate and δ18Ophosphate to determine diagenetic state is not recommended. The strength of this correlation observed in bones and teeth is variable and alternate indicators of diagenetic state (i.e. C:N ratios of collagen) provide more robust and independent evidence of isotope preservation despite presence/absence of a strong isotope correlation. Published 2012. This article is a U.S. Government work and is in the public domain in the USA.  相似文献   

15.
We report here on the measurements of carbon and nitrogen stable isotopes of bone collagen from the Middle Byzantine site of Kastella, in the city of Heraklion, on the island of Crete, Greece. The data derived from the analysis suggest a diet based primarily on terrestrial, C3 protein, probably from animal sources, with the inclusion of some marine protein. The adult diet at this site is relatively uniform, with no detectable differences between average isotopic values for males and females. We also found that bone collagen δ15N values for a small number of juveniles decreased to adult levels after the age of two years, indicating that weaning occurred at or before this age. Copyright © 2006 John Wiley & Sons, Ltd.  相似文献   

16.
Intra‐individual variations in carbon (δ13C) and nitrogen (δ15N) isotope measurements of dentine collagen in ungulate teeth can be related to diet and environmental changes at different periods during the life of the animal. A protocol of serial sampling of first, second and third molar roots was applied to modern caribou (17–27 months old) of the Qamanirjuaq herd (Rangifer tarandus groenlandicus), Canada. Based on a previous study, we predicted that M2 would reflect winter, M3 summer and M1 a complete year in terms of the isotopic record. Relatively high δ15N values (ca. 6 to 8‰), previously attributed to winter stress, were found in different molars of different specimens, reflecting a period of growth between April 1966 to April 1967. Previous results on other teeth from the same population confirmed that a high δ15Ncoll value signal corresponded to the winter of 1966/67. This temporary increase in δ15N value was probably linked to diet and/or environmental change. Collagen from M1 reflects the first winter whereas M2 and M3 reflect the second winter of life of young caribou. A longer time record including summer is represented by the bone collagen of the mandible. Results obtained on molar roots and mandible bone of the modern caribou of Banks Island herd (Rangifer tarandus pearyi) confirmed this seasonal record. Such collagen isotopic analysis on M1, M2 and M3 roots and jawbone can be applied to reindeer found in archaeological sites. Mandibles retaining deciduous premolars are preferable to avoid the possible loss of the winter tooth signal observed in animals older than 2 years. Copyright © 2010 John Wiley & Sons, Ltd.  相似文献   

17.
The Sabana de Bogotá in the northern Andes is an interesting region to investigate temporal patterns of dietary variation because it counts with a vast archeological and osteological record for the last 10,000 years. In this paper, stable isotope data of human archeological bone collagen and apatite were used to study the evolution of diet and major subsistence transformations taking place during the Holocene (~9000–600 cal BP). Paleoenvironmental reconstructions and the isotopic ecology of the Sabana de Bogotá were used as an interpretative baseline. Stable isotope measurements (δ13Ccol, δ13Cap, δ15N, and Δ13Ccol-ap) representing hunter-gatherers, horticulturalists, and agriculturalists (N = 134 individuals) were analyzed by using bivariate, regressional, and discriminant statistical techniques. Results show that early Holocene hunter-gatherers (9000–7000 cal BP) consumed mostly C3 vegetal resources locally available. In contrast, animal protein was less important. Middle Holocene hunter-gatherers (6000–4500 cal BP) continued with the food foraging pattern observed in the earlier counterparts and presented a slight increase in C3 animal protein intake. During the initial late Holocene ca. 4000 cal BP, important shifts in subsistence strategies occurred when populations presented a trend toward mixed C3/C4 diets, and by ca. 3500 cal BP, there is a clear signal of C4 crops (i.e., maize) consumption concomitant with the introduction of ceramic technology. During the final late Holocene (last 2000 cal years BP), intensive agriculture was adopted and humans presented relatively diverse diets integrated by C4 and C3 crops, C3-C4 feeding animals, and freshwater resources. Such dietary change coincides with an increase in sociopolitical complexity, population size, and a general decline in health.  相似文献   

18.
Incremental dentine analysis utilizes tissue that does not remodel and that permits comparison, at the same age, of those who survived infancy with those who did not at high temporal resolution. Here, we present a pilot study of teeth from a 19th‐century cemetery in London, comparing the merits of two methods of obtaining dentine increments for subsequent isotope determination. Covariation in δ13C and δ15N values suggests that even small variations have a physiological basis. We show that high‐resolution intra‐dentine isotope profiles can pinpoint short‐duration events such as dietary change or nutritional deprivation in the juvenile years of life.  相似文献   

19.
We analyse the isotopic values (δ13C, δ15N) of the diet of pre-Columbian horticulturalist populations from tropical and subtropical areas of southeastern South America, belonging to the Guarani and Taquara archaeological units. The data indicate different trends in each one (T?=?4.21; P?=?0.0004), showing a mixed diet with maize consumption in the Guarani samples (δ13Cco?=??15.5?±?1.8‰; δ13Cap ?10.4?±?0.8‰) and a depleted one in the Taquara ones (δ13Cco ?18.2?±?1.7‰; δ13Cap ?11.9?±?0.9‰), with a significant internal dispersion in both populations. The first population has higher nitrogen values (δ15N 11.1?±?0.6‰) compared to the Taquara samples (δ15N 9.3?±?1‰), suggesting a more carnivorous diet. The recognition of these pre-Columbian mixed diets involves the identification of maize cultivation on the Atlantic side of the southernmost area of South America (Parana Delta, 34° SL). Through the analysis of δ18O we have identified two isotopic ecozones, the first along the Paraná River Valley, with an average value of δ18O ?3.7?±?0.5‰ (CV?=?13.5%; CI?=??3.83 / ?3.16), and the second one, located in the Planalto of southern Brazil (Araucaria Forest), with a mean value of δ18O ?1.5?±?0.3‰ (CV?=?16.5%; CI?=??1.69 / ?1.29). The isotopic data (δ13C, δ15N and δ18O) suggest human movements between these two ecozones.  相似文献   

20.
The examination of isotope ratios from multiple tissues offers new life to interpretations of commingled assemblages where information regarding individual biological history has been lost. Here, life histories from a commingled sample of Byzantine monks were reconstructed using enamel and bone δ13C and δ15N values. The δ13C values suggest a diet dominated by C3 products, while the δ15N ratios indicate variable contributions of animal protein. After correcting for tissue‐specific enrichment factors, bone δ13C values were significantly enriched over enamel; this may be due to an increase in protein consumption, but could also reflect structural differences between tissues or correction factors used to compare these data.  相似文献   

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