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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
31

Bitumen in Neolithic Iran: Biomolecular and isotopic evidence.

Gregg, M.W., Brettell, Rhea C., Stern, Ben January 2007 (has links)
No / This paper presents the results of the chemical analysis of materials recovered from two of the earliest agricultural villages in southwestern Iran and a late Neolithic pastoral encampment in nearby Khuzistan. Gas chromatography - mass spectrometry (GC-MS) revealed biomarker compounds characteristic of bitumen in residues from ceramic vessels supporting the excavators¿ contention that the interior surfaces of some vessels were coated with a thin layer of such material and confirmed that ¿fragments¿ collected during excavation were indeed bitumen. Biomolecular and isotopic analysis of the bitumen indicated that the sources utilized lie in the Susa and Deh Luran regions of southwestern Iran. / NERC (MSc); AHRC (PhD)
32

Using stable isotope analysis to identify Irish migrants in the Catholic Mission of St Mary and St Michael, Whitechapel

Beaumont, Julia, Montgomery, Janet, Wilson, Andrew S. January 2013 (has links)
No
33

An investigation of the origins of cattle and aurochs deposited in the Early Bronze Age barrows at Gayhurst and Irthlingborough

Towers, Jacqueline R., Montgomery, Janet, Evans, J., Jay, Mandy, Parker Pearson, M. 2009 October 1916 (has links)
Yes / The Early Bronze Age round barrows at Irthlingborough, Northamptonshire and Gayhurst, Buckinghamshire contained remarkably large quantities of cattle (Bos taurus) remains. At Irthlingborough, at least 185 skulls with smaller numbers of mandibles, shoulder blades and pelves were found together with a small number of skeletal elements from aurochs (Bos primigenius). In contrast, the remains from Gayhurst are dominated by the limb bones from more than 300 animals. This study employed strontium isotope ratio analysis of cattle tooth enamel from 15 cattle and one aurochs to investigate the diversity of the animals’ origins at both sites and provide insights into Early Bronze Age funerary practices. Although strontium results show that most of the cattle and the aurochs included in this study were consistent with local origins, one animal from each barrow was born remotely, most likely in western Britain. In addition, a second Gayhurst animal was consistent with origins in a region of chalk rather than the local Jurassic sediments.
34

A new method for investigating the relationship between diet and mortality: hazard analysis using dietary isotopes

Redfern, R.C., DeWitte, S.N., Beaumont, Julia, Millard, A.R., Hamlin, C. 30 August 2019 (has links)
Yes / Bioarchaeological and clinical data show that diet influences health, and this relationship is crucial to how we understand past health with respect to sex and age. We propose a new method that coinvestigates the relationship between mortality risk and diet in the past. Our method integrates dietary stable isotope data (δ13 Carbon and δ 15 Nitrogen) from Roman Britain (N=659) with hazards analysis. The results show that these data can be informatively used in this type of analysis in general, and that in the context of Roman Britain, higher δ 13C is associated with lower risks of mortality while higher δ 15N is associated with elevated risks of mortality. Importantly, the results emphasize that a bioarchaeological approach to interpretation must be taken in order to more fully understand the results obtained by the method
35

Fish Bones, Isotopes, and Microscopes: A Pilot Study in Applying Analytical Methods to Iron Age Faunal Remains

22 March 2022 (has links)
Yes / Previous research on the Iron Age in Britain has argued that no fishing occurred during this period in Britain. This argument has now been complicated by large assemblages of fish bones that have been excavated from Iron Age sites in the Northern Isles. Further investigation into this issue became the focus of the author's MSc dissertation research in 2016, specifically on the recently excavated fish bone assemblages from the site of Swandro on Rousay, Orkney. Analytical methods, including stable isotope analysis and scanning electron microscopy, were applied in an attempt to determine how the fish may have been utilised at the site. Results have revealed evidence that could be interpreted as fishing activity and possible consumption by humans at Swandro. This paper disseminates and further examines these results and considers how this particular project is useful as a pilot study in the application of analytical methodologies to problematic faunal remains such as fish, and why this could be important to future zooarchaeological and environmental archaeological research.
36

Kinship practices in Early Iron Age southeast Europe: genetic and isotopic analysis of burials from the Dolge njive barrow cemetery, Dolenjska, Slovenia

Armit, I., Fischer, C-E., Koon, Hannah E.C., Nicholls, Rebecca A., Olalde, I., Rohland, N., Buckberry, Jo, Montgomery, J., Mason, P., Cresnar, M., Buster, L., Reich, D. 02 August 2022 (has links)
Yes / DNA analysis demonstrates that all seven individuals buried in an Early Iron Age barrow at Dolge njive, southeast Slovenia, are close biological relatives. Although group composition does not suggest strict adherence to a patrilineal or matrilineal kinship system, the funerary tradition appears highly gendered, with family links through both the male and female line being important in structuring communities. We explore the implications for our understandings of kinship and funerary practices in Early Iron Age southeast Europe. / This research forms part of ENTRANS: a collaborative project involving the Universities of Bradford, Zagreb and Ljubljana, and the Institute for the Protection of Cultural Heritage of Slovenia. ENTRANS (PI: Armit) received funding from the European Union’s Seventh Framework Programme for research, technological development and demonstration under grant agreement no 291827. The project is financially supported by the HERA Joint Research Programme (www.heranet.info) which is co-funded by AHRC, AKA, BMBF via PT-DLR, DASTI, ETAG, FCT, FNR, FNRS, FWF, FWO, HAZU, IRC, LMT, MHEST, NWO, NCN, RANNÍS, RCN, VR and The European Community FP7 2007-2013, under the Socioeconomic Sciences and Humanities programme. Research for this paper also received funding from the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation programme under grant agreement No 834087 (COMMIOS). The ancient DNA work was supported by NIH grant GM100233, John Templeton Foundation grant 61220, the Howard Hughes Medical Institute, and the Allen Discovery Center program, a Paul G. Allen Frontiers Group advised program of the Paul G. Allen Family Foundation.
37

Assessment of nutritional stress in famine burials using stable isotope analysis

Walter, B.S., DeWitte, S.N., Dupras, T., Beaumont, Julia 03 April 2020 (has links)
Yes / Objectives: We compared δ15N and δ13C values from bone and dentine collagen profiles of individuals interred in famine‐related and attritional burials to evaluate whether individuals in medieval London who experienced nutritional stress exhibit enriched nitrogen in bone and tooth tissue. Dentine profiles were evaluated to identify patterns that may be indicative of famine during childhood and were compared with the age of enamel hypoplasia (EH) formation to assess whether isotopic patterns of undernutrition coincide with the timing of physiological stress. Materials and Methods: δ15N and δ13C isotope ratios of bone collagen were obtained from individuals (n = 128) interred in attritional and famine burials from a medieval London cemetery (c. 1120–1539). Temporal sequences of δ15N and δ13C isotope profiles for incrementally forming dentine collagen were obtained from a subset of these individuals (n = 21). Results: Results indicate that individuals from attritional graves exhibit significantly higher δ15N values but no significant differences were found between burial types for the sexes. Analyses of dentine profiles reveal that a lower proportion of famine burials exhibit stable dentine profiles and that several exhibit a pattern of opposing covariance between δ15N and δ13C. EH were also observed to have formed during or after the opposing covariance pattern for some individuals. Conclusions: The results of this study may reflect differences in diet between burial types rather than nutritional stress. Though nutritional stress could not be definitively identified using bone and dentine collagen, the results from dentine analysis support previous observations of biochemical patterns associated with nutritional stress during childhood. / Division of Behavioral and Cognitive Sciences. Grant Numbers: BCS‐1261682, BCS‐1540208. Office of the Vice President for Research, University of South Carolina. Grant Number: SPARC Fellowship Grant
38

Nitrogen transformations at the Kiruna mine : The use of stable nitrogen isotopes to trace nitrogen-transforming processes

Nilsson, Lino January 2013 (has links)
Release of different nitrogen compounds can cause eutrophication in lakes and rivers whichcan lead to oxygen-free environments in bottom water and in the sediment and can in turnlead to fish-deaths. Ammonium can be toxic to biota and nitrate can in high concentrationeven be toxic to humans. WHO has released a limit for nitrate concentration in drinking waterof 10mg/l. The LKAB mine in Kiruna is the largest underground iron mine in the world and isprospecting, mining and refining iron ore, with an annual production of around 28 milliontons. Release of different nitrogen compounds as a result of the explosives used during themining operations has been a known problem for some time; however the processes affectingnitrogen during the water transport have never been fully investigated. The main objective of this MSc thesis is to determine if changes in nitrogen and oxygenisotope composition can be used as a tracer for nitrogen transformation processes in the minewater at LKABs underground mine in Kiruna. Water samples were collected at key points in the water transport system and were analyzedfor isotopic composition. Isotopic and chemical data revealed two different sources of nitrateand ammonium, undetonated explosives and leachate from waste rocks. Three differentnitrogen changing processes affecting concentration of nitrate and ammonium were found:ammonium volatilization, nitrification and sorption. It was not possible to quantify theseprocesses individually. No processes which decrease the nitrate concentration were found.
39

Climate change, water stress and agriculture in the Indus Civilisation, 3000-1500 BC

Jones, Penelope Jean January 2018 (has links)
This thesis investigates the relationship between climate, agriculture and social change in South Asia’s Bronze Age urban Indus Civilisation. Specifically, my research tests the hypothesis that an abrupt weakening of the Indian Summer Monsoon ca 2100 cal BC led to increasing crop water stress, and hence potentially contributed to the Civilisation’s decline by reducing food supply. This hypothesis is frequently invoked in discussions of the Civilisation’s end, yet until now, has not been empirically tested. Using material excavated from several Indus settlements, this study uses a novel combination of isotopic techniques to directly test the connection between climate change and agricultural stress. These techniques are first, oxygen isotope analysis of faunal bones and teeth; and second, stable carbon isotope analysis of crop remains. The oxygen analyses provide detailed records of monsoon intensity at a local, human scale, while the carbon analyses provide an empirical test of whether crop water stress increased. Applied in parallel across a diverse suite of Indus sites, these techniques together provide an archaeologically and ecologically-nuanced analysis of climatic impacts. The archaeological analyses are supported by a methodological study, which investigates how water status relates to the stable carbon isotope signature in barley (Hordeum vulgare) and the Indian jujube (Ziziphus mauritiana) along a climatic transect in north-western India today. Overall, the isotopic results suggest that at the sites sampled here, climate change probably had minimal impacts on crop water availability. This does not necessarily mean that climate change had no impacts on agriculture across the greater Indus sphere, and indeed there are hints that there may have been climatic stress in more vulnerable settings. However, at the sites studied here, any hydrological consequences of climate change—including the 4.2 ka event—appear to have had neither a lasting nor a pervasive impact on the adequacy of crop water supply. This is an important finding, and necessitates a clear refinement of how we think about climatic sensitivity, climatic vulnerability, and climatic impacts across—and indeed beyond—the greater Indus.
40

Food web structure and variation in the Gila river, USA

Pilger, Tyler Jess January 1900 (has links)
Master of Science / Department of Biology / Keith B. Gido / The upper Gila River basin in southwest New Mexico, USA is one of the few unimpounded drainage basins in North America and is a stronghold for the unique and endemic fishes west of the Continental Divide. Multiple non-indigenous fishes have been introduced to the Gila River and are a potential threat to native fishes, yet very little is known of the trophic ecology of the native and nonnative fishes. We used diet and stable isotopes collected from native and nonnative fishes to identify their trophic relationships and evaluate potential interactions in the upper Gila River basin during June-July, 2007 and 2008. Diet and stable isotope data indicated aquatic invertebrates were the primary food for both native and nonnative fishes. Native large-bodied fishes were mainly algivore/detritivores and native small-bodied fishes were primarily insectivores. Small-bodied nonnative fishes fed on detritus and aquatic invertebrates. Nonnative predators preyed on small-bodied fishes and predaceous aquatic invertebrates and had higher trophic positions than all native fishes. Although nonnative predators did not rely exclusively on native fishes as prey, their presence extended community food-chain lengths, and the combined predation on juvenile native fishes by multiple apex predators may threaten persistence of native fishes. The lack of concise evidence for negative effects suggested that impacts of nonnative predators were more subtle and confirmed the underlying complexity of a relatively simple community The extensive database on feeding relations of Gila River fishes allowed us to further understand how energy moves through ecosystems. Specifically, the goal of chapter two was to characterize variation in fish-community food web structure within and among study reaches on the Gila River using [superscript]13C and [superscript]15N stable isotopes. We hypothesized that food web structure would reflect variation in fish community structure, resource availability and environmental conditions across habitats. Food web structure in isotope bi-plot space was estimated using community-wide measures of trophic structure, mean trophic position, and food-chain length. Permutational multivariate analysis of variance indicated that indices of food web structure were more variable among than within reaches and this pattern was primarily associated with variation in trophicl area occupied by taxa in isotope bi-plot space and mean trophic position of those taxa. Variation in food web structure was significantly associated with fish species richness across macrohabitats but was weakly associated with abiotic reach-scale factors. Variation in food web structure was concordant with variation in fish community composition and suggested that factors influencing the distribution of fishes also influence food web structure.

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