Life history of the individuals buried in the St. Benedict Cemetery (Prague, 15th–18th Centuries): Insights from 14C dating and stable isotope (δ13C, δ15N, δ18O) analysis

Funerary practices and bioarchaeological (sex and age) data suggest that a mortality crisis linked to an epidemic episode occurred during the fifth phase of the St. Benedict cemetery in Prague (Czech Republic). To identify this mass mortality episode, we reconstructed individual life histories (dietary and mobility factors), assessed the population's biological homogeneity, and proposed a new chronology through stable isotope analysis (δ¹³C, δ¹⁸O and δ¹⁵N) and direct radiocarbon dating. Stable isotope analysis was conducted on the bone and tooth enamel (collagen and carbonate) of 19 individuals from three multiple graves (MG) and 12 individuals from individual graves (IG). The δ¹⁵N values of collagen and the difference between the δ¹³C values of collagen and bone carbonate could indicate that the IG individuals had a richer protein diet than the MG individuals or different food resources. The human bone and enamel carbonate and δ¹⁸O values suggest that the majority of individuals from MG and all individuals from IG spent most of their lives outside of the Bohemian region. Variations in δ¹⁸O values also indicate that all individuals experienced residential mobility during their lives. The stable isotope results, biological (age and sex) data and eight ¹⁴C dates clearly differentiate the MG and IG groups. The present work provides evidence for the reuse of the St. Benedict cemetery to bury soldiers despite the funeral protest ban (1635 AD). The Siege of Prague (1742 AD) by French‐Bavarian‐Saxon armies is identified as the cause of the St. Benedict mass mortality event. Am J Phys Anthropol 151:202–214, 2013. © 2013 Wiley Periodicals, Inc.     

Dietary variation within and between populations of northeast Atlantic killer whales,Orcinus orca,inferred from δ13C and δ15N analyses

Epidermal skin samples from eastern North Atlantic killer whales, Orcinus orca, were analyzed for carbon and nitrogen stable isotope ratios. From those, comparisons within a data set of 17 samples collected from Tysfjord, Norway, in November suggested that diet is relatively specialized during this time period at this location. There were significant differences between a small set of samples from Iceland and those collected from Norway, which had all been assigned to the same population by a previous population genetics study. The results would be consistent with matrilines feeding on either the Norwegian or Icelandic stocks of Atlantic herring (Clupea harengus). There was no significant difference within Icelandic samples between those assigned to the population known to feed upon herring and those assigned to a population hypothesized to follow Atlantic mackerel (Scomber scombrus). The greatest differences were between the epidermal samples analyzed in this study and tooth and bone collagen samples from the North Sea that were analyzed previously, which also showed significantly more variation in isotopic ratios than found for skin samples. These differences could reflect differences in turnover rate, differences in diet‐tissue fractionation and discrimination due to the amino acid composition of the different tissues, and/or greater competition promoting dietary variation between groups in the North Sea.     

The influence of lipid‐extraction and long‐term DMSO preservation on carbon (δ13C) and nitrogen (δ15N) isotope values in cetacean skin

Stable isotope analysis (SIA) has rapidly become a useful tool to study the ecology of wild animal populations, especially for elusive, wide‐ranging predators like marine mammals. The development of projectile biopsy techniques resulted in the collection of thousands of cetacean tissue samples that were archived in a dimethyl sulfoxide (DMSO) solution for long‐term, multidecadal preservation. Here we examine the influence of DMSO preservation on carbon (δ¹³C) and nitrogen (δ¹⁵N) values by comparing a set of paired delphinid skin samples stored frozen without preservative and in DMSO for up to 22 yr. Treatment of paired frozen and DMSO‐preserved skin in a 2:1 chloroform:methanol solution yielded similar δ¹³C and δ¹⁵N values, revealing that DMSO and lipid contamination have similar isotopic effects on skin, and that these effects can be removed using routine lipid‐extraction methods. Further, amino acid concentrations in DMSO‐preserved and frozen skin tissue were similar, providing independent evidence of minimal protein alteration due to preservation. Access to a rich archive of skin samples preserved in DMSO will expand our ability to examine temporal and spatial variability in the isotope values of cetaceans, which will aid our understanding of how their ecology has been influenced by historical changes in environmental conditions.     

Evidence for seasonal variation in δ13C and δ18O profiles of Baculites and implications for growth rate

The life histories of ammonites and the life strategies they employed are difficult to assess without robust modern analogues but placing constraints on ammonite growth rates provides a fundamental first step to understanding this abundant, but poorly understood, fossil group. Here we interpret periodic variations in carbon and oxygen stable isotope profiles from Campanian and Maastrichtian ammonites (Baculites) as seasonally driven and use these records to determine their rate of shell precipitation. Several of these samples are housed in museums and were originally prepared using sealants for display and preservation but testing of these sealants indicated no alteration of the isotopic values of treated carbonate. Diagenetic alteration, as determined by shell microstructure, affected the preservation of isotopic signals, resulting in the loss of seasonal variation in less well‐preserved specimens, and the δ¹³C signal is more robust than δ¹⁸O. The periodicity of isotopic profiles from Baculites shells presented here suggest that these organisms grew at rapid rates (c. 340 mm per year), which may imply an r‐type life strategy in which the animals reach maturity quickly, spawn large quantities of progeny, and die at a young age. Because of the potential mobility of Baculites, reconstructing palaeoenvironmental conditions from these isotopic records is challenging and should be conducted cautiously. Unfortunately, well‐preserved Baculites shells much longer than 350 mm are rarely recovered, which complicates the statistical treatment of potential periodicity in isotopic profiles.     

Technical note: A new method for measuring long bone curvature using 3D landmarks and semi‐landmarks

Here we describe and evaluate a new method for quantifying long bone curvature using geometric morphometric and semi‐landmark analysis of the human femur. The technique is compared with traditional ways of measuring subtense and point of maximum curvature using either coordinate calipers or projection onto graph paper. Of the traditional methods the graph paper method is more reliable than using coordinate calipers. Measurement error is consistently lower for measuring point of maximum curvature than for measuring subtense. The results warrant caution when comparing data collected by the different traditional methods. Landmark data collection proves reliable and has a low measurement error. However, measurement error increases with the number of semi‐landmarks included in the analysis of curvature. Measurements of subtense can be estimated more reliably using 3D landmarks along the curve than using traditional techniques. We use equidistant semi‐landmarks to quantify the curve because sliding the semi‐landmarks masks the curvature signal. Principal components analysis of these equidistant semi‐landmarks provides the added benefit of describing the shape of the curve. These results are promising for functional and forensic analysis of long bone curvature in modern human populations and in the fossil record. Am J Phys Anthropol, 2010. © 2010 Wiley‐Liss, Inc.     

A phylogenetic perspective on species diversity, β‐diversity and biogeography for the microbial world

There is an increasing interest to combine phylogenetic data with distributional and ecological records to assess how natural communities arrange under an evolutionary perspective. In the microbial world, there is also a need to go beyond the problematic species definition to deeply explore ecological patterns using genetic data. We explored links between evolution/phylogeny and community ecology using bacterial 16S rRNA gene information from a high‐altitude lakes district data set. We described phylogenetic community composition, spatial distribution, and β‐diversity and biogeographical patterns applying evolutionary relatedness without relying on any particular operational taxonomic unit definition. High‐altitude lakes districts usually contain a large mosaic of highly diverse small water bodies and conform a fine biogeographical model of spatially close but environmentally heterogeneous ecosystems. We sampled 18 lakes in the Pyrenees with a selection criteria focused on capturing the maximum environmental variation within the smallest geographical area. The results showed highly diverse communities nonrandomly distributed with phylogenetic β‐diversity patterns mainly shaped by the environment and not by the spatial distance. Community similarity based on both bacterial taxonomic composition and phylogenetic β‐diversity shared similar patterns and was primarily structured by similar environmental drivers. We observed a positive relationship between lake area and phylogenetic diversity with a slope consistent with highly dispersive planktonic organisms. The phylogenetic approach incorporated patterns of common ancestry into bacterial community analysis and emerged as a very convenient analytical tool for direct inter‐ and intrabiome biodiversity comparisons and sorting out microbial habitats with potential application in conservation studies.     

Higher β‐ and γ‐diversity at species and genetic levels in headwaters than in mid‐order streams in Hydropsyche (Trichoptera)

相似文献   

Decrypting stable‐isotope (δ13C and δ15N) variability in aquatic plants

相似文献   

Solution properties of γ‐crystallins: Compact structure and low frictional ratio are conserved properties of diverse γ‐crystallins

γ‐crystallins are highly specialized proteins of the vertebrate eye lens where they survive without turnover under high molecular crowding while maintaining transparency. They share a tightly folded structural template but there are striking differences among species. Their amino acid compositions are unusual. Even in mammals, γ‐crystallins have high contents of sulfur‐containing methionine and cysteine, but this reaches extremes in fish γM‐crystallins with up to 15% Met. In addition, fish γM‐crystallins do not conserve the paired tryptophan residues found in each domain in mammalian γ‐crystallins and in the related β‐crystallins. To gain insight into important, evolutionarily conserved properties and functionality of γ‐crystallins, zebrafish (Danio rerio) γM2b and γM7 were compared with mouse γS and human γD. For all four proteins, far UV CD spectra showed the expected β‐sheet secondary structure. Like the mammalian proteins, γM7 was highly soluble but γM2b was much less so. The heat and denaturant stability of both fish proteins was lower than either mammalian protein. The ability of full‐length and truncated versions of human αB‐crystallin to retard aggregation of the heat denatured proteins also showed differences. However, when solution behavior was investigated by sedimentation velocity experiments, the diverse γ‐crystallins showed remarkably similar hydrodynamic properties with low frictional ratios and partial specific volumes. The solution behavior of γ‐crystallins, with highly compact structures suited for the densely packed environment of the lens, seems to be highly conserved and appears largely independent of amino acid composition.     

Intraskeletal isotopic compositions (δ13C, δ15N) of bone collagen: Nonpathological and pathological variation

Paleodiet research traditionally interprets differences in collagen isotopic compositions (δ¹³C, δ¹⁵N) as indicators of dietary distinction even though physiological processes likely play some role in creating variation. This research investigates the degree to which bone collagen δ¹³C and δ¹⁵N values normally vary within the skeleton and examines the influence of several diseases common to ancient populations on these isotopic compositions. The samples derive from two medieval German cemeteries and one Swiss reference collection and include examples of metabolic disease (rickets/osteomalacia), degenerative joint disease (osteoarthritis), trauma (fracture), infection (osteomyelitis), and inflammation (periostitis). A separate subset of visibly nonpathological skeletal elements from the German collections established normal intraindividual variation. For each disease type, tests compared bone lesion samples to those near and distant to the lesions sites. Results show that normal (nonpathological) skeletons exhibit limited intraskeletal variation in carbon‐ and nitrogen‐isotope ratios, suggesting that sampling of distinct elements is appropriate for paleodiet studies. In contrast, individuals with osteomyelitis, healed fractures, and osteoarthritis exhibit significant intraskeletal differences in isotope values, depending on whether one is comparing lesions to near or to distant sites. Skeletons with periostitis result in significant intraskeletal differences in nitrogen isotope values only, while those with rickets/osteomalacia do not exhibit significant intraskeletal differences. Based on these results, we suggest that paleodiet researchers avoid sampling collagen at or close to lesion sites because the isotope values may be reflecting both altered metabolic processes and differences in diet relative to others in the population. Am J Phys Anthropol 153:598–604, 2014. © 2013 Wiley Periodicals, Inc.     

Host identification in unfed ticks from stable isotope compositions (δ13C and δ15N)

Determination of the ratios of natural stable isotopes (¹³C/¹²C and ¹⁵N/¹⁴N) in unfed Ixodes ricinus nymphs and adults, which, in their previous stage, fed on captive wild rodents (Apodemus sylvaticus and Myodes glareolus), wild birds (Parus major and Cyanistes caeruleus) or domestic ruminants (Ovis aries and Bos taurus), demonstrated that it is possible to identify each host category with confidence. First, the tick–blood spacing, which is the difference between values obtained from ticks and the blood of hosts that they had fed on in the previous stage, was consistent (152 spacings investigated from 15 host individuals in total). Second, potential confounding factors (tick age and sex) did not affect the discriminatory power of the isotope patterns, nor did different rearing conditions (room temperature vs. 4 °C) or the duration of development (maximum of 430 days). The findings that the tick–blood isotope spacings, across a diverse range of hosts, were similar and predictable, and that confounders had little or no effect on this, strongly support the usage of the isotope approach. Because each of the host categories has a different role in the population dynamics of I. ricinus and in tick‐borne pathogen ecology, the method described here has great potential for the clarification of tick and tick‐borne pathogen ecology in the field.     

Comparative response of δ13C, δ18O and δ15N in durum wheat exposed to salinity at the vegetative and reproductive stages

This study compared the performance of the stable isotope composition of carbon (δ¹³C), oxygen (δ¹⁸O) and nitrogen (δ¹⁵N) by tracking plant response and genotypic variability of durum wheat to different salinity conditions. To that end, δ¹³C, δ¹⁸O and δ¹⁵N were analysed in dry matter (dm) and the water‐soluble fraction (wsf) of leaves from plants exposed to salinity, either soon after plant emergence or at anthesis. The δ¹³C and δ¹⁸O of the wsf recorded the recent growing conditions, including changes in evaporative conditions. Regardless of the plant part (dm or wsf), δ¹³C and δ¹⁸O increased and δ¹⁵N decreased in response to stress. When the stress conditions were established just after emergence, δ¹⁵N and δ¹³C correlated positively with genotypic differences in biomass, whereas δ¹⁸O correlated negatively in the most severe treatment. When the stress conditions were imposed at anthesis, relationships between the three isotope signatures and biomass were only significant and positive within the most severe treatments. The results show that nitrogen metabolism, together with stomatal limitation, is involved in the genotypic response to salinity, with the relative importance of each factor depending on the severity and duration of the stress as well as the phenological stage that the stress occurs.     

Validation of a field‐ready handheld meter for plasma β‐hydroxybutyrate analysis

Plasma metabolite analysis is frequently used to assess the energetic state and energy intake of birds. Plasma β‐hydroxybutyrate (BUTY) is a common metabolite used in these studies, and is correlated with fasting and mass loss. BUTY is typically quantified in laboratory assays that are costly, time‐consuming, and prone to human error. We tested the accuracy and precision of a field‐ready handheld BUTY meter. We compared BUTY concentration values obtained in the laboratory and with the handheld meter in plasma samples from 19 Grasshopper Sparrows (Ammodramus savannarum), and assessed precision with repeat analysis of a single sample. The handheld meter reported BUTY concentrations in < 2 min, was highly precise, and as accurate as the laboratory assay method—all ideal for field conditions. Collecting blood samples for laboratory analysis, particularly from remote field sites, involves a series of risks and challenges for permitting or the logistics of storage and shipping, as well as the associated costs. Analyzing samples on site, whether with the unit we tested or other similar handheld meters, makes plasma metabolite analysis practical and possible in field conditions and for taxa where this technique has been underused due to permitting, transport, or other logistical constraints of laboratory analysis methods. The cost of analysis is similar on a per sample basis, but, without the need to store and transport samples, using handheld meters in the field may be cheaper.     

The legacy of enhanced N and S deposition as revealed by the combined analysis of δ13C, δ18O and δ15N in tree rings

This study aimed to evaluate the effects of long‐term repeated aerial nitrogen (N) and sulphur (S) misting over tree canopies of a Sitka spruce plantation in Scotland. We combined δ¹³C and δ¹⁸O in tree rings to evaluate the changes in CO₂ assimilation (A) and stomatal conductance (g_s) and to assess their contribution to variations in the intrinsic water‐use efficiency (WUE_i, i.e., the A/g_s ratio). Measurements of δ¹⁵N enabled shifts in the ecosystem N cycling following misting to be assessed. We found that: (i) N applications, with or without S, increased the ratio between A and g_s in favour of A, thus supporting a fertilizer effect of added N. (ii) After the treatments ceased, the trees quickly adjusted to the reductions of N deposition, but not to the reduction in S deposition, which had a negative effect on WUE_i by reducing A. This indicates that the beneficial role of N deposition may be negated in forests that previously received a high load of acid rain. (iii) δ¹⁵N in tree rings reflected the N dynamics caused by canopy retention, with the fingerprint also present in the litter, after the experiment stopped. (iv) Both our results (obtained using canopy applications) and a collection of published data (obtained using soil applications) showed that generally WUE_i increased in response to an increase of N applications, with the magnitude of the changes related to soil conditions and the availability of other nutrients. The shifts observed in δ¹⁵N in tree rings also suggest that both the quantity of the applied N and its quality, mediated by processes occurring during canopy N retention, are important determinants of the interactions between N and C cycles. Stable isotopes are useful probes to understand these processes and to put the results of short‐term experiments into context.     

Technical note: comparison of the Maresh reference data with the who international standard for normal growth in healthy children

The Maresh reference data on stature and long bone lengths in a sample of healthy middle-class children from Denver, Colorado [Maresh: Am J Dis Child 66 (1943) 227-257; Maresh: Am J Dis Child 89 (1955) 725-742; Maresh: Human growth and development (1970) p 155-200], have been used extensively by biological anthropologists to estimate juvenile age and body size using skeletal elements and to assess growth in skeletal series from different ethnic populations or archaeological cultural groups. How well these data reflect the potentially diverse growth patterns of healthy human populations from different geographic areas is unknown. Similarly, the efficacy of using the Maresh reference data to estimate stunting prevalence in prehistoric populations is unknown. This report presents the results from a comparison of the Maresh data on supine length and standing height to the World Health Organization (WHO) international child growth standard. The WHO growth standard is meant to depict typical human growth under optimal conditions and can be used to assess children worldwide, regardless of ethnicity and socioeconomic status. The results from this comparison indicate that although the Maresh reference data generally conform to the WHO standard, reflecting a normal human growth pattern, and therefore serve as a suitable reference for comparative studies of growth patterns, these reference data are not suitable for estimating stunting prevalence.     

Cyclic strain induces reorganization of integrin α5β1 and α2β1 in human umbilical vein endothelial cells

Cyclic strain has been shown to modulate endothelial cell (EC) morphology, proliferation, and function. We have recently reported that the focal adhesion proteins focal adhesion kinase (pp125^FAK) and paxillin, are tyrosine phosphorylated in EC exposed to strain and these events regulate the morphological change and migration induced by cyclic strain. Integrins are also localized on focal adhesion sites and have been reported to induce tyrosine phosphorylation of pp125^FAK under a variety of stimuli. To study the involvement of different integrins in signaling induced by cyclic strain, we first observed the redistribution of α and β integrins in EC subjected to 4 h cyclic strain. Human umbilical vein endothelial cells (HUVEC) seeded on either fibronectin or collagen surfaces were subjected to 10% average strain at a frequency 60 cycles/min. Confocal microscopy revealed that β₁ integrin reorganized in a linear pattern parallel with the long axis of the elongated cells creating a fusion of focal adhesion plaques in EC plated on either fibronectin (a ligand for α₅β₁) or collagen (a ligand for α₂β₁) coated plates after 4 h exposure to cyclic strain. β₃ integrin, which is a vitronectin receptor, did not redistribute in EC exposed to cyclic strain. Cyclic strain also led to a reorganization of α₅ and α₂ integrins in a linear pattern in HUVEC seeded on fibronectin or collagen, respectively. The expression of integrins α₅, α₂, and β₁ did not change even after 24 h exposure to strain when assessed by immunoprecipitation of these integrins. Cyclic strain-induced tyrosine phosphorylation of pp125^FAK occurred concomitant with the reorganization of β₁ integrin. We concluded that α₅β₁ and α₂β₁ integrins play an important role in transducing mechanical stimuli into intracellular signals. J. Cell. Biochem. 64:505–513. © 1997 Wiley-Liss, Inc.     

Moss δ13C: an accurate proxy for past water environments in polar regions

Increased aridity is of global concern. Polar regions provide an opportunity to monitor changes in bioavailable water free of local anthropogenic influences. However, sophisticated proxy measures are needed. We explored the possibility of using stable carbon isotopes in segments of moss as a fine‐scale proxy for past bioavailable water. Variation in δ¹³C with water availability was measured in three species across three peninsulas in the Windmill Islands, East Antarctica and verified using controlled chamber experiments. The δ¹³C from Antarctic mosses accurately recorded long‐term variations in water availability in the field, regardless of location, but significant disparities in δ¹³C between species indicated some make more sensitive proxies. δ¹³C_SUGAR derived from living tissues can change significantly within the span of an Antarctic season (5 weeks) in chambers, but under field conditions, slow growth means that this technique likely represents multiple seasons. δ¹³C_CELLULOSE provides a precise and direct proxy for bioavailable water, allowing reconstructions for coastal Antarctica and potentially other cold regions over past centuries.