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The Limfjord is a sound in Northern Jutland, Denmark, connecting the North Sea with the Kattegat. A multi-proxy approach has been applied to a sediment core from Kilen, a former fjord arm near the town of Struer, to reveal the Limfjord’s development in more detail. In this paper, we concentrate on radiocarbon dating of shells and on stable isotope measurements of bulk sediment from 7400 to 1300 cal BP.Reservoir ages in coastal waters and estuaries can differ considerably from the global model ocean. The seas around Denmark have a reservoir age of c. 400 years, while a hardwater effect of a few thousand years is possible for freshwater with a high content of dissolved carbonate. On the other hand, freshwater without a significant content of 14C-dead carbon does not have a reservoir age. In coastal waters, the different water sources mix and produce highly variable reservoir ages.Due to Holocene relative sea level fluctuations, caused by the interplay of eustatic sea level changes and isostasy, the Limfjord had varying connections to the sea. As the relative proportion of marine and fresh water varied with time, the reservoir age for the Limfjord is also expected to vary. Radiocarbon datings of shells, compared to a terrestrial age model, resulted in reservoir ages with Delta-R values between -150 and +320 years. The d13C and C/N values of bulk organic matter follow a line which endpoints are the values of terrestrial and marine plants, respectively. The relative contribution of the two sources of organic matter can thus be estimated. The d13C and C/N inferred salinity can be related to changes in Delta-R and other palaeoenvironmental proxies. An increasing marine influence throughout the largest part of the core is followed by large variations around 2000 cal BP.

Since the publication of the 775 AD cosmic-ray event in 2012 there has been an increased focus world-wide on producing annual high precision 14C measurements. At the Aarhus AMS Centre (AARAMS), a project has been initiated in close collaboration with astronomers and geoscientists to investigate the 11-year solar cycle during low solar activity periods in particular. So far, our focus has been on the Spörer (AD 1450 – 1550) and Oort (AD 1040 – 1080) grand solar minima. We have also, however, investigated the AD 775 and AD 994 cosmic-ray events; the latter at sub-annual resolution by 14C dating both early and late wood fractions from single years. Additionally, we have produced annual 14C data covering the periods from AD 650 – 750 and AD 800 – 900. The presented annual records are all made on the late-wood fraction from Danish oak trees only to ensure univocally a single year origin of the carbon. We will discuss the data in relation to published annual data as well as the existing data integrated in IntCal13. We believe that our datasets will provide a valuable contribution for updating the international calibration curve to annual resolution for the last 2000 years. Further, we will report on the laboratory procedures used at AARAMS for producing the annual 14C data.

The North Water Polynya (NOW) is host to an exceptionally large number of seabirds, which gather in large colonies over the brief summer months. These birds link marine and terrestrial ecosystems as they rely on the productivity of the marine polynya for their sustenance but use the terrestrial environment as breeding sites. Here, we examine how the little auk (Alle alle), alters freshwater and terrestrial ecosystems using stable isotope ratios (δ15N and δ13C) of freshwater and terrestrial biota, terrestrial vegetation indices and physical–chemical properties, productivity and community structure of fresh waters in catchments with and without little auk colonies. We then examine the long-term patterns of presence, absence and abundance of a range seabirds across the NOW using palaeoecological approaches. Lake sediment core were taken fromlakes within little auk colonies on Salva Ø and at Annikitsoq on the Cape York peninsula. Peat cores were extracted at sites with little auk colonies at Søkongdale, Annikitsoq, and Robertson fjord, from Eider duck colonies at Three Sister Bees and Booth Sound and from a thick billed Murre colony on Saunders Island. δ15N values provided an unequivocal signature of bird arrival at the lake sites, whereas radiometric dating of the basal sample of a peat deposit provides a minimum maximum age. 14C dating of the peat cores suggest that eider and thick billed mure have a long history of presence in the NOW going back over 5000 years. Whereas the little auk colonies appear the have arrived at the coring sites 4300 years before present, whereas the peat cores are dated to circa 2400 years BP. We discuss how the arrival and abundance of bird colonies may relate to Holocene climate variation and the history of human habitation.

Quartär – Internationales Jahrbuch zur Erforschung des Eiszeitalters und der Steinzeit, Bd. 60 (2013): Quartär. Internationales Jahrbuch zur Eiszeitalter- und Steinzeitforschung

In-situ cosmogenic nuclides demonstrate existence of landforms preserved under glacial ice in regions such as Northern Sweden (Fabel, 2002), Svalbard (Gjermundsen, 2015) and New England (Bierman, 2015). Elsewhere, the existence of relict landforms is inferred from landscape morphology. Low-relief mountain summits along Sognefjorden in Norway have in the past been used as a base for re-constructing a regional pre-Quaternary surface (Nesje, 1994). The underlying assumption of this approach is that Quaternary surface processes eroded the summits very little, and the reconstructed surface can then be used to determine the total Quaternary bedrock erosion between the summits. However, the amount of Quaternary erosion of these summit flats remains debated (e.g. Steer, 2012) Here, we present an extensive new dataset of in-situ produced cosmogenic 10Be and 26Al in bedrock and boulders from high and flat summits along a 200 km long transect from the coast to the inner parts of Sognefjorden. Our results indicate substantial glacial modification of the summits within the last 50 ka. Close to the coast, at an elevation of around 700 meters, the cosmogenic nuclide signal was reset around the Younger Dryas. Further inland, our results indicate very little cosmogenic nuclide inheritance prior to the last deglaciation. We do not find any signs of exceptional longevity of the low-relief landscape around Sognefjord. In contrast, our results indicate that the low-relief areas were continuously eroded by glacial and periglacial processes in the Quaternary, and that excluding recent erosion of the summits is likely to underestimate total Quaternary erosion. Bierman et al. Cold-based Laurentide ice covered New England’s highest summits during the Last Glacial Maximum. Geology 43(12), 1059-1062, 2015. Fabel et al. Landscape preservation under Fennoscandian ice sheets determined from in situ produced 10 Be and 26 Al. Earth and Planetary Science Letters 201(2), 397-406, 2002. Gjermundsen et al. Minimal erosion of Arctic alpine topography during late Quaternary glaciation. Nature Geoscience 8(10), 789-792, 2015. Nesje & Whillans. Erosion of Sognefjord, Norway. Geomorphology 9(1), 33-45, 1994. Steer et al. Bimodal Plio-Quaternary glacial erosion of fjords and low-relief surfaces in Scandinavia. Nature Geoscience 5(9), 635-639, 2012.

It is an ongoing debate whether the degree of chemical weathering in mountain regolith can be used to infer a pre-Quaternary formation history (e.g. Strømsøe and Paasche, 2011; Goodfellow 2012). Here we present a new dataset of in-situ produced cosmogenic 10Be and 26Al along with sediment analyses from five pit profiles dug through regolith mantle on the easternmost summits of Reinheimen Nationalpark in Norway. The study area only shows sporadic signs of glacial erosion, and could be classified as a relict non-glacial surface. We aim to use the residence time of regolith in this area to infer rates of landscape evolution of the mountain summit.ReferencesGoodfellow B W, 2012. A granulometry and secondary mineral fingerprint of chemical weathering in periglacial landscapes and its application to blockfield origins. Quaternary Science Reviews, 57, 121- 135.Strømsøe J R, Paasche Ø, 2011. Weathering patterns in high-latitude regolith. Journal of Geophysical Research: Earth Surface, 116 (F3)

Homeobox genes are often deregulated in cancer and can have both oncogenic and tumor-suppressing potential. The Caudal-related homeobox transcription factor 2 (CDX2) is an intestine-specific transcription factor. CDX2 has been implicated in differentiation, proliferation, cell adhesion, and migration. In this study, we investigated CDX2 mRNA and protein expression in relation to the clinicopathological characteristics of colon cancer, including mismatch repair status and recurrence risk.Tumor samples were obtained from colon cancer patients. Biopsies from tumor tissue and normal adjacent tissue were fixed in liquid nitrogen for RNA extraction or in formalin and paraffin embedded (FFPE) for immunohistochemical staining. CDX2 mRNA expression was evaluated by RT-qPCR. FFPE sections were stained for MLH1, MSH2, MSH6, PMS2, and CDX2.A total of 191 patient samples were included in the study and analyzed by immunohistochemistry. Of these samples, 97 were further evaluated by RT-qPCR. There was no significant difference in CDX2 mRNA expression between tumor and normal tissues. CDX2 mRNA expression was significantly lower in right-sided tumors (p0.05), poorly differentiated tumors (p0.05), and MMR-deficient tumors (p0.05). Similarly, CDX2 protein expression was more often low or absent in right-sided tumors (p0.01), poorly differentiated tumors (p0.001), and MMR-deficient tumors (p0.001). Low CDX2 protein or mRNA expression was not associated with recurrence risk.We found that CDX2 downregulation is associated with MMR deficiency, right-sided tumors, and poor differentiation at both the mRNA and protein level. Whether CDX2 plays an active role in tumor progression in MSI/MMR-deficient tumors remains to be elucidated.

We are currently performing high-precision radiocarbon dating of annual tree ring samples to construct a new calibration curve for the period AD 650-900. We will present preliminary results from the intervals AD 650-750 and AD 800-900. The period AD 750-800 is covered by the poster by Fogtmann-Schulz et al. (session A6).The new calibration curve will be used for high-precision dating of the stratigraphy of Ribe, the oldest town in Scandinavia and an important site for the chronology of the Viking age. Many Viking Age artefact types are dated based on their stratigraphical position in the Ribe sequence. The older layers, containing preserved timber, are well-dated by dendrochronology. However, not all of the phases in Ribe have been dated by absolute dating methods yet. The latest dendro-date is AD 741, but activities at the site continue more than 100 years after that date. The calendar ages of some important typological reference points for Viking Age chronology are thus only estimated by relative methods, e.g., the duration of phases derived from the thickness of the layers. Therefore, a precise radiocarbon chronology of the entire occupation history of Ribe has the potential to consolidate or shift the dating of important artefact types. Our measurements could thus have an impact on Viking Age chronology in general. As Ribe was embedded in global networks of transcontinental trade, reflected by finds such as Early Islamic trade commodities, our results have the potential to resonate in the wider research field of urban networks.We are developing an age model for the Viking Age activities at Ribe based on the ongoing excavations by the Northern Emporium project. We will present the first radiocarbon dates from Ribe and will illustrate the effect of using different calibration curves based on decadal or annual samples.

To investigate the expression of interleukin-6 (IL6) in colon cancer tissue, and to examine if the risk of relapse is influenced by IL6 expression.Fresh-frozen biopsies from tumor and normal adjacent tissues were taken from patients with colon cancer during surgery and stored at -80 °C. mRNA expression for interleukin-6 was evaluated with reverse transcription real time quantitative polymerase chain reaction. Survival analyses were carried-out using a Cox competing risk regression model.IL6 mRNA was significantly more highly expressed in tumor tissue compared to normal adjacent tissue (p0.001). We found no significant association with regard to IL6 expression and histological differentiation or cancer stage. We found a significant association between high IL6 expression and risk of relapse (Hazard Ratio=2.23, 95% CI=1.10-4.53; p0.05), also when adjusted for clinicopathological characteristics (Hazard Ratio=2.16, 95% CI=1.07-4.40; p0.05).Interleukin-6 is up-regulated in colon cancer tissue at the transcriptional level and is significantly associated with increased risk of relapse.

At Hjarnø, an island in Horsens fjord (Denmark), a submerged Mesolithic settlement has been known since at least 1936. In 2010 and 2011, a refuse layer of the former settlement was excavated. Despite the threat of erosion, organic preservation was generally good. For example, fragments of paddles with remains of painted decorations were found. In 2015, a shell layer at the site, facing imminent destruction by waves, was sampled. In total, 8 large boxes of shells were collected, one from each of the 1m² squares.A sample of ca. 18.000 shells NISP (ca. 3000 MNI) from the eight squares was identified to species. Of these, a subsample of 780 cockles and 115 oysters were measured. Preliminary results show that oysters became on average larger and cockles smaller moving up the sequence, as the species dominating the assemblages shifted from oysters to cockles. Overall, several lines of evidence, including the taphonomy of the shells, suggest that the shell accumulation is anthropogenic.Radiocarbon dates of associated shell and charcoal samples were used to calculate the local reservoir effect and to establish the chronology of the shell midden. Interestingly, our results indicate that the change in dominant species, from oysters to cockles, happened at about 5300 cal BC. The orthodoxy is that this shift in mollusc species occurred at 4000 cal BC and a hypothesis for the introduction of the Neolithic economy was partly driven by ‘the oyster decline’. We will also present δ¹³C and δ¹⁸O measurements on CO₂ subsamples from the shells, which will enable us to study the marine environment in more detail.

Authors thank the National Natural Science Foundation of China grants NSFC 41888101 and NSFC 41731174, the 111 program of China (D19002), U.S. NSF Grant 1702816, and the Malcolm H. Wiener Foundation for support for research that contributed to the IntCal20 curve. The work on the Swiss and German YD trees was funded by the German Science foundation and the Swiss National Foundation (grant number: 200021L_157187). The operation in Aix-en-Provence is funded by the EQUIPEX ASTER-CEREGE, the Collège de France and the ANR project CARBOTRYDH (to EB). The work on the correlation of tree ring 14C with ice core 10Be was partially supported by the Swedish Research Council and the Knut and Alice Wallenberg foundation. M. Butzin is supported by the German Federal Ministry of Education and Research (BMBF) through the PalMod project (grant number: 01LP1505B). S. Talamo and M. Friedrich. are funded by the European Research Council under the European Union’s Horizon 2020 Research and Innovation Programme (grant agreement No. 803147-RESOLUTION, awarded to ST). C. Turney would like to acknowledge support of the Australian Research Council (FL100100195 and DP170104665). P. Reimer and W. Austin acknowledge the support of the UKRI Natural Environment Research Council (Grant NE/M004619/1). Radiocarbon (14C) ages cannot provide absolutely dated chronologies for archaeological or paleoenvironmental studies directly but must be converted to calendar age equivalents using a calibration curve compensating for fluctuations in atmospheric 14C concentration. Although calibration curves are constructed from independently dated archives, they invariably require revision as new data become available and our understanding of the Earth system improves. In this volume the international 14C calibration curves for both the Northern and Southern Hemispheres, as well as for the ocean surface layer, have been updated to include a wealth of new data and extended to 55,000 cal BP. Based on tree rings, IntCal20 now extends as a fully atmospheric record to ca. 13,900 cal BP. For the older part of the timescale, IntCal20 comprises statistically integrated evidence from floating tree-ring chronologies, lacustrine and marine sediments, speleothems, and corals. We utilized improved evaluation of the timescales and location variable 14C offsets from the atmosphere (reservoir age, dead carbon fraction) for each dataset. New statistical methods have refined the structure of the calibration curves while maintaining a robust treatment of uncertainties in the 14C ages, the calendar ages and other corrections. The inclusion of modeled marine reservoir ages derived from a three-dimensional ocean circulation model has allowed us to apply more appropriate reservoir corrections to the marine 14C data rather than the previous use of constant regional offsets from the atmosphere. Here we provide an overview of the new and revised datasets and the associated methods used for the construction of the IntCal20 curve and explore potential regional offsets for tree-ring data. We discuss the main differences with respect to the previous calibration curve, IntCal13, and some of the implications for archaeology and geosciences ranging from the recent past to the time of the extinction of the Neanderthals. Publisher PDF