72 research outputs found
A sedimentary model for transverse inland dunes in central Scandinavia
The largest dune fields in Sweden and Norway are small in international comparison but still form distinct parts of this previously glaciated landscape. The dunes formed c.10.5-9 ka ago, shortly after the last deglaciation, when winds close to the ice sheet were strong and vegetation was largely absent [1-4]. Since then they have been more or less stable and today they are covered by forest. Most of the dunes are curvi-linear in shape and formed transverse to the wind [5]. Here we present a sedimentary model for these transverse inland dunes, based on geophysical and sedimentological investigations of dunes at Skattungheden, Bonäsheden and Starmoen in central Sweden and south-eastern Norway. Ground-penetrating radar profiles reveal the main architectural elements of the dunes, while logging of sediment exposures in the dunes provide information on sedimentary structures. Grain-size analysis and scanning electron microscope studies of individual grains give us more detail on sediment characteristics.The main dune body, consisting of cross beds generally dipping 25-30°, makes up the largest part of the dunes; minor elements include windward side cover, dune-crest superimposed features and dune-toe apron (Fig. 1). The dominating sediment structures are planar parallel lamination, massive to vaguely stratified beds and a few types of secondary structures, such as bioturbation or physical disturbances. Few large erosional discordances are seen, and the dominating depositional processes are wind-ripple migration and some grain fall on the sloping lee sides. The sediments are well-sorted fine-to-medium sand, dominated by quartz, but with significant amounts of feldspar as well as some lithic fragments, micas and heavy minerals. Most grains are angular to subrounded and their surfaces display few traces of aeolian transport. Overall, the dune sands show large similarities to their source material (glacifluvial deposits), which suggests only short transport and brief reworking by aeolian processes.References[1] Alexanderson, H. and M. Bernhardson, OSL dating and luminescence characteristics of aeolian deposits and their source material in Dalarna, central Sweden Boreas, 2016. 45: p. 876-893.[2] Alexanderson, H. and M. Henriksen, A short-lived aeolian event during the Early Holocene in southeastern Norway. Quaternary Geochronology, 2015. 30: p. 175-180.[3] Bernhardson, M. and H. Alexanderson, Early Holocene NW-W winds reconstructed from small dune fields, central Sweden. Boreas, 2018.[4] Alexanderson, H. and D. Fabel, Holocene chronology of the Brattforsheden delta and inland dune field, SW Sweden. Geochronometria, 2015. 42: p. 1-16.[5] Bernhardson, M. and H. Alexanderson, Early Holocene dune field development in Dalarna, central Sweden: A geomorphological and geophysical case study. Earth Surface Processes and Landforms, 2017. 42: p. 1847-1859
BIGCCS Innovations – Measures to Accelerate CCS Deployment
AbstractAfter six years in operation, BIGCCS International Research Centre is in its final phase, and results are being produced at high speed. The ultimate goal for the BIGCCS centre is to contribute to the acceleration of deployment of CCS technologies. Therefore, the Centre has put considerable emphasis on generating useful results to its industrial partners, and results with a significant potential for commercialization. The paper describes 22 of the most promising innovations identified under the Centre. These 22 innovations are related to capture, transport, storage and value chain, and are but a few of all potential innovations identified. The paper also discusses how BIGCCS has managed innovations, which are classified according to a nine-point Technology Readiness Level scheme
Branched GDGT variability in sediments and soils from catchments with marked temperature seasonality
acceptedVersio
Ancient DNA and osteological analyses of a unique paleo-archive reveal Early Holocene faunal expansion into the Scandinavian Arctic.
Paleo-archives are essential for our understanding of species responses to climate warming, yet such archives are extremely rare in the Arctic. Here, we combine morphological analyses and bulk-bone metabarcoding to investigate a unique chronology of bone deposits sealed in the high-latitude Storsteinhola cave system (68°50' N 16°22' E) in Norway. This deposit dates to a period of climate warming from the end of the Late Glacial [~13 thousand calibrated years before the present (ka cal B.P.)] to the Holocene thermal maximum (~5.6 ka cal B.P.). Paleogenetic analyses allow us to exploit the 1000s of morphologically unidentifiable bone fragments resulting in a high-resolution sequence with 40 different taxa, including species not previously found here. Our record reveals borealization in both the marine and terrestrial environments above the Arctic Circle as a naturally recurring phenomenon in past periods of warming, providing fundamental insights into the ecosystem-wide responses that are ongoing today
Rare variants with large effects provide functional insights into the pathology of migraine subtypes, with and without aura
Publisher Copyright: © 2023, The Author(s).Migraine is a complex neurovascular disease with a range of severity and symptoms, yet mostly studied as one phenotype in genome-wide association studies (GWAS). Here we combine large GWAS datasets from six European populations to study the main migraine subtypes, migraine with aura (MA) and migraine without aura (MO). We identified four new MA-associated variants (in PRRT2, PALMD, ABO and LRRK2) and classified 13 MO-associated variants. Rare variants with large effects highlight three genes. A rare frameshift variant in brain-expressed PRRT2 confers large risk of MA and epilepsy, but not MO. A burden test of rare loss-of-function variants in SCN11A, encoding a neuron-expressed sodium channel with a key role in pain sensation, shows strong protection against migraine. Finally, a rare variant with cis-regulatory effects on KCNK5 confers large protection against migraine and brain aneurysms. Our findings offer new insights with therapeutic potential into the complex biology of migraine and its subtypes.Peer reviewe
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