Rapid ice sheet retreat triggered by ice stream debuttressing: Evidence from the North Sea

Using high-resolution bathymetric and shallow seismic data from the North Sea, we have mapped hitherto unknown glacial landforms that connect and resolve longstanding gaps in the Quaternary geological history of the basin. We use these data combined with published information and dates from sediment cores to reconstruct the extent of the Fennoscandian and British Ice Sheets (FIS and BIS) in the North Sea during the last phases of the last glacial stage. It is concluded that the BIS occupied a much larger part of the North Sea than previously suggested and that North Sea ice underwent a dramatic disintegration ~18,500 yr ago. This was triggered by grounding-line retreat of the Norwegian Channel Ice Stream, which debuttressed adjacent ice masses, and led to an unzipping of the BIS and FIS accompanied by drainage of a large ice-dammed lake. Our reconstruction of events provides an opportunity to improve understanding and modeling of the disintegration of marine-based ice sheets, and the complex interplay between ocean circulation and the cryosphere

Early Quaternary sedimentary processes and palaeoenvironments in the central North Sea

A number of elongate trough-like features are observed in the early Quaternary succession of the central North Sea basin. A definitive model of formation for the features remains unclear but the troughs may aid in our understanding of the depositional environment of the early Quaternary. In total, 380 troughs were mapped over 11 000 km2 using continuous 3D seismic data and analysed in conjunction with well log data and understanding of the probable palaeogeographical context. The troughs were formed in a marine setting on the slope of a large clinoform set during a period of rapid progradation. The geometry and infill of the troughs, as well as the marine setting, strongly support a model of repeated density-driven downslope flows which excavate and then infill the troughs perpendicular to the strike of the slope. A subset of the troughs are observed to form parallel to the strike in such a way that cannot be easily explained by downslope processes alone. A number of possible models are considered for the formation of these along-slope troughs; here we conclude that the most likely scenario involves modification of the downslope flows by currents which divert the features along-slope while maintaining the erosive nature of the flow

Facebook Uses: How and Why? Uses and Gratifications Keeping Up With the Technology

With currently more than 200 million active users, Facebook represents the most popular social network site today. My thesis is a qualitative study examining how and why people use Facebook. Uses and gratifications perspective is used as the theoretical back bone as well as the way of researching. The thesis is testing the relevance of the uses and gratifications motives as defined by previous research studies and combining them with the ideas of persuasive technology. Several psychological aspects as the norm of reciprocity, need to belong and impression management are added to the discussion. By considering previous research, the influence of technology as well as psychological motives for social interaction, I present an overview of the relevant motives for Facebook use. This thesis contributes to raising the knowledge about how and why people use social network sites as well as updating uses and gratification theory in order for it to be applicable to the modern media.MEVI350MASV-MEV

Prothrombotic Single Nucleotide Polymorphisms and Risk of Myocardial Infarction: A Narrative Review of the Literature

Background: Environmental risk factors for myocardial infarction (MI) have been extensively investigated. In addition, family history of MI is an important risk factor for the disease. Several prothrombotic genotypes are well-established risk factors for venous thrombosis. However, the role of prothrombotic genotypes as risk factors for arterial thrombosis is less emphasized. Aim: To create a general overview of the existing literature on the role of non-O/O blood type, Prothrombin G20210A and Factor V Leiden; the main genetic determinants of thrombophilia, as risk factors for incident MI. Methods: A narrative literature review of studies published after 2005 was performed. The biomedical databases Medline and Embase were used in a structured literature search regarding the association between non-O/O blood type, Prothrombin G20210A and Factor V Leiden as risk factors for MI. Relevant MeSH terms for exposure and outcome were combined in the Ovid search platform; a common search software for the two databases. Results: Several meta-analyses have been published during the recent years and report modest effects of non-O blood type (ORs ranging from 1.1 to 1.3), Prothrombin G20210A (ORs around 1.4) and Factor V Leiden (ORs ranging from 1.2 to 1.9) on the risk of MI. For Prothrombin G20210A, the adjusted OR for ST-elevation myocardial infarction (STEMI) for carriers versus non-carriers of the risk allele was 2.2 (95% CI: 1.1-4.3) among subjects <35 years. Moreover, when compared to wild genotype carriers, Factor V Leiden heterozygous or homozygous mutant carriers were more likely associated with a trend towards more severe coronary artery disease (CAD) (OR 1.85; 95% CI 1.26-2.72 and OR 3.70; 95% CI 1.71-8.00). Conclusion: In conclusion, the existing literature supports an association between non-O blood type, Prothrombin G20210A and Factor V Leiden and risk of MI. The Prothrombin G20210A and Factor V Leiden variants seem to be associated with premature adverse events and more severe CAD

Mid-Pleistocene thin-skinned glaciotectonic thrusting of the Aberdeen Ground Formation, Central Graben region, central North Sea

This paper presents the results of a high-resolution 2D seismic survey of mid-Pleistocene glaciogenic sediments in the Central Graben region of the central North Sea. Sediments have undergone major glaciotectonic thrusting and folding associated with the repeated southerly advance of a mid-Pleistocene ice sheet. The total observed length of the thrust-stacked section is approximately 5–6 km, comprising a series of discrete thrust slices, which range in length from  700 m. The basal detachment of the thrust complex occurs at a depth of ca. 220 m below the sea bed within the upper Aberdeen Ground Formation. A thin-skinned glaciotectonic model involving proglacial to ice-marginal glaciotectonic thrusting followed by post-tectonic deposition is proposed. Initial ice advance led to the over-pressurizing of groundwater within a laterally extensive sand sheet in the upper Aberdeen Ground Formation, promoting the formation of a major décollement surface at the base of the developing thrust-stack. Over-pressurization of the groundwater system is thought to have occurred in response to rapid ice advance, suggesting that the development of large-scale thrust complexes may be associated with surge-type behaviour. The proposed model evidences complex dynamics of mid-Pleistocene ice sheets within the central North Sea

Latitudinal variability in the Quaternary development of the Eurasian ice sheets—Evidence from the marine domain

Here we present the first compilation of sediment volumes, sedimentation rates, and chronology of Quaternary sediment packages along the entire marine margin of the Eurasian ice sheets (EurIS; British–Irish, Kara–Barents Sea–Svalbard, and Fennoscandian). This compilation allows for a subdivision of the EurIS development into three phases (2.6–1.5 Ma, 1.5–0.78 Ma, and 0.78–0 Ma). At the start of the Quaternary, sedimentation rates increased, relative to pre-Quaternary rates, by an order of magnitude. This abruptness in rate change excludes tectonic raising of landmasses as the main factor, but more likely reflects climate change through increased glacial erosion. The sediment distribution data suggest that the Kara–Barents Sea–Svalbard Ice Sheet (KBSIS) already was quite large at the beginning of the Quaternary, and well before 1.5 Ma it extended to the shelf edge and coalesced with the Fennoscandian Ice Sheet (FIS), which prior to 1.5 Ma most likely was located near the coast. Large ice streams and intense glacial erosion characterized the KBSIS in the 1.5–0.78 Ma time period, whereas the FIS at that time extended farther out on the continental shelf. After 0.78 Ma, a north-south change in EurIS development occurred. In the FIS and the British–Irish Ice Sheet (BIIS), large ice streams developed and shelf-edge glaciations occurred nearly 1 m.y. later compared to the KBSIS. The FIS and BIIS also repetitively coalesced in the North Sea. A significant drop in sediment input along the KBSIS marine margin, to the lowest Quaternary level, suggests a less erosive KBSIS.publishedVersio

Patient–clinician interactions in shared diabetes/nephrology consultations:A qualitative observation study

Background: The incidence of chronic disease is increasing worldwide which, in turn, increases the demand for healthcare services. To meet these demands, healthcare systems are adapting their services in order to reduce treatment costs and ensure coherence for patients with multiple diseases. One form of adaptation is shared outpatient consultations between internal medical specialties. However, little is known about how patients interact with multiple clinicians in shared consultations. Aim: This project aimed to explore how patients with diabetes and chronic kidney disease interact with multiple clinicians in a shared outpatient setting. Research Methods: We performed a qualitative ethnographic study, combining focused participant observations with informal field interviews. We included 17 participants, nine males and eight females with a mean age of 67.3 in the project. The data analysis was guided by Braun and Clarke's reflexive thematic analysis and Arthur Kleinman's theory of illness and disease. Results: We found one over-arching theme: ‘A consultation which encompassed both illness and disease’ and four subthemes: (1) ‘The medical focal point’ pertained to the focus on physiological measurements in dialogue between patients and clinicians. (2) ‘The possibility of negotiations’ illustrated how decisions about dialysis and pharmacological treatment were based on negotiations. (3) ‘Speaking different languages’ displayed how patients used alternative illness-based explanations whereas clinicians tended to use biomedical language. (4) ‘Perceptions of everyday life’ concerned what patients considered was best for them when managing their illness and everyday lives. Conclusion: Patients present information on how they balance life with physiological and psychosocial challenges. When clinicians employ a biomedical perspective, opportunities to gain information on patients' illness behaviours or cues to negotiate are missed. Patients prioritise functioning on a daily level over following treatment regimes. These findings are tenuous and require verification in similar studies in similar settings. Short Phrases: Shared Outpatient Clinic, Patient–clinician interactions.</p

Pasts of the Present

In light of today’s global boom in landmark architecture, urban megaprojects and reconstructions of cultural heritage buildings, this paper analyses two large-scale reconstruction projects at iconic historical locations in Japan: the Heijō Palace in Nara and Dejima in Nagasaki. Since the 1990s, the two projects have recreated long-lost built environments, gradually transforming the sites, turning them into museums and exhibition spaces and giving rise to thorough reform of the surrounding urban fabric. In this paper I trace the involved agents’ motivations to engage in historical reconstruction from early-phase experimental efforts to legitimise the sites’ protected status to present-day politico-economic mobilisations of important historical locations to boost city attraction values. In this way, I link these two unfolding projects in Nara and Nagasaki to issues of urban boosterism, heritage production and the facilitation and commodification of tourist experiences of past realities. Approaching the reconstructions as contemporary heritage in traditional guise, the paper argues that both sites revolve materially, spatially and thematically around the master-metaphors of flow, growth and intercultural connectivity that characterise the present age. Elucidating processes of authentication and intersections of ideological and economic interests in and around the two sites, the paper asks in what ways Japanese cities exploit lost iconic localities and reconstructed heritage under post-industrial conditions marked by globalisation and intense cultural-economic competition

Increased fluid flow activity in shallow sediments at the 3 km Long Hugin Fracture in the central North Sea

The North Sea hosts a wide variety of seafloor seeps that may be important for transfer of chemical species, such as methane, from the Earth's interior to its exterior. Here we provide geochemical and geophysical evidence for fluid flow within shallow sediments at the recently discovered, 3-km long Hugin Fracture in the Central North Sea. Although venting of gas bubbles was not observed, concentrations of dissolved methane were significantly elevated (up to six-times background values) in the water column at various locations above the fracture, and microbial mats that form in the presence of methane were observed at the seafloor. Seismic amplitude anomalies revealed a bright spot at a fault bend that may be the source of the water column methane. Sediment porewaters recovered in close proximity to the Hugin Fracture indicate the presence of fluids from two different shallow (<500m) sources: (i) a reduced fluid characterized by elevated methane concentrations and/or high levels of dissolved sulfide (up to 6 mmol L−1), and (ii) a low-chlorinity fluid (Cl ∼305 mmol L−1) that has low levels of dissolved methane and/or sulfide. The area of the seafloor affected by the presence of methane-enriched fluids is similar to the footprint of seepage from other morphological features in the North Sea

Ice wedges as archives of winter palaeoclimate: a review

Ice wedges are a characteristic feature of northern permafrost landscapes and grow mainly by snowmelt that refreezes in thermal contraction cracks that open in winter. In high latitudes the stable‐isotope composition of precipitation (δ18O and δD) is sensitive to air temperature. Hence, the integrated climate information of winter precipitation is transferred to individual ice veins and can be preserved over millennia, allowing ice wedges to be used to reconstruct past winter climate. Recent studies indicate a promising potential of ice‐wedge‐based paleoclimate reconstructions for more comprehensive reconstructions of Arctic past climate evolution. We briefly highlight the potential and review the current state of ice‐wedge paleoclimatology. Existing knowledge gaps and challenges are outlined and priorities for future ice‐wedge research are suggested. The major research topics are (1) frost cracking and infilling dynamics, (2) formation and preservation of the stable‐isotope information, (3) ice‐wedge dating, (4) age‐model development and (5) interpretation of stable‐isotope time series. Progress in each of these topics will help to exploit the paleoclimatic potential of ice wedges, particularly in view of their unique cold‐season information, which is not adequately covered by other terrestrial climate archives