| 1. |
- Abazov, V. M., et al.
(författare)
-
The upgraded DO detector
- 2006
-
Ingår i: Nuclear Instruments and Methods in Physics Research Section A. - : Elsevier BV. - 0168-9002 .- 1872-9576. ; 565:2, s. 463-537
-
Tidskriftsartikel (refereegranskat)abstract
- The DO experiment enjoyed a very successful data-collection run at the Fermilab Tevatron collider between 1992 and 1996. Since then, the detector has been upgraded to take advantage of improvements to the Tevatron and to enhance its physics capabilities. We describe the new elements of the detector, including the silicon microstrip tracker, central fiber tracker, solenoidal magnet, preshower detectors, forward muon detector, and forward proton detector. The uranium/liquid -argon calorimeters and central muon detector, remaining from Run 1, are discussed briefly. We also present the associated electronics, triggering, and data acquisition systems, along with the design and implementation of software specific to DO.
|
|
| 2. |
- Acharya, B. S., et al.
(författare)
-
Introducing the CTA concept
- 2013
-
Ingår i: Astroparticle physics. - : Elsevier BV. - 0927-6505 .- 1873-2852. ; 43, s. 3-18
-
Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)abstract
- The Cherenkov Telescope Array (CTA) is a new observatory for very high-energy (VHE) gamma rays. CTA has ambitions science goals, for which it is necessary to achieve full-sky coverage, to improve the sensitivity by about an order of magnitude, to span about four decades of energy, from a few tens of GeV to above 100 TeV with enhanced angular and energy resolutions over existing VHE gamma-ray observatories. An international collaboration has formed with more than 1000 members from 27 countries in Europe, Asia, Africa and North and South America. In 2010 the CTA Consortium completed a Design Study and started a three-year Preparatory Phase which leads to production readiness of CTA in 2014. In this paper we introduce the science goals and the concept of CTA, and provide an overview of the project. (C) 2013 Elsevier B.V. All rights reserved.
|
|
| 3. |
|
|
| 4. |
|
|
| 5. |
- Actis, M., et al.
(författare)
-
Design concepts for the Cherenkov Telescope Array CTA : an advanced facility for ground-based high-energy gamma-ray astronomy
- 2011
-
Ingår i: Experimental astronomy. - : Springer. - 0922-6435 .- 1572-9508. ; 32:3, s. 193-316
-
Tidskriftsartikel (refereegranskat)abstract
- Ground-based gamma-ray astronomy has had a major breakthrough with the impressive results obtained using systems of imaging atmospheric Cherenkov telescopes. Ground-based gamma-ray astronomy has a huge potential in astrophysics, particle physics and cosmology. CTA is an international initiative to build the next generation instrument, with a factor of 5-10 improvement in sensitivity in the 100 GeV-10 TeV range and the extension to energies well below 100 GeV and above 100 TeV. CTA will consist of two arrays (one in the north, one in the south) for full sky coverage and will be operated as open observatory. The design of CTA is based on currently available technology. This document reports on the status and presents the major design concepts of CTA.
|
|
| 6. |
|
|
| 7. |
- Dahl-Jensen, D., et al.
(författare)
-
Eemian interglacial reconstructed from a Greenland folded ice core
- 2013
-
Ingår i: Nature. - : Springer Science and Business Media LLC. - 0028-0836 .- 1476-4687. ; 493:7433, s. 489-494
-
Tidskriftsartikel (refereegranskat)abstract
- Efforts to extract a Greenland ice core with a complete record of the Eemian interglacial (130,000 to 115,000 years ago) have until now been unsuccessful. The response of the Greenland ice sheet to the warmer-than-present climate of the Eemian has thus remained unclear. Here we present the new North Greenland Eemian Ice Drilling ('NEEM') ice core and show only a modest ice-sheet response to the strong warming in the early Eemian. We reconstructed the Eemian record from folded ice using globally homogeneous parameters known from dated Greenland and Antarctic ice-core records. On the basis of water stable isotopes, NEEM surface temperatures after the onset of the Eemian (126,000 years ago) peaked at 8 +/- 4 degrees Celsius above the mean of the past millennium, followed by a gradual cooling that was probably driven by the decreasing summer insolation. Between 128,000 and 122,000 years ago, the thickness of the northwest Greenland ice sheet decreased by 400 +/- 250 metres, reaching surface elevations 122,000 years ago of 130 +/- 300 metres lower than the present. Extensive surface melt occurred at the NEEM site during the Eemian, a phenomenon witnessed when melt layers formed again at NEEM during the exceptional heat of July 2012. With additional warming, surface melt might become more common in the future.
|
|
| 8. |
- Cirasuolo, M., et al.
(författare)
-
MOONS: the Multi-Object Optical and Near-infrared Spectrograph for the VLT
- 2014
-
Ingår i: Ground-based and Airborne Instrumentation for Astronomy V. - : SPIE. - 1996-756X .- 0277-786X. ; 9147, s. 91470-91470
-
Konferensbidrag (refereegranskat)abstract
- MOONS (the Multi-Object Optical and Near-infrared Spectrograph) has been selected by ESO as a third-generation instrument for the Very Large Telescope (VLT). The light grasp of the large collecting area offered by the VLT (8.2m diameter), combined with the large multiplex and wavelength coverage (optical to near-IR: 0.8 -1.8 mu m) of MOONS will provide the European astronomical community with a powerful, unique instrument able to pioneer a wide range of Galactic, extragalactic and cosmological studies, and it will provide crucial follow-up for major facilities such as Gaia, VISTA, Euclid and LSST. MOONS has the observational power needed to unveil galaxy formation and evolution over the entire history of the Universe, from stars in our Milky Way, through the redshift desert, and up to the epoch of very first galaxies and reionization of the Universe at redshifts of z > 8-9, just a few million years after the Big Bang. From five years of observations MOONS will provide high-quality spectra for > 3M stars in our Galaxy and the Local Group, and for 1-2M galaxies at z > 1 (for an SDSS-like survey), promising to revolutionize our understanding of the Universe. The baseline design consists of similar to 1000 fibres, deployable over a field-of-view of similar to 500 arcmin(2), the largest patrol field offered by the Nasmyth focus at the VLT. The total wavelength coverage is 0.8 -1.8 mu m with two spectral resolving powers: in the medium-resolution mode (R similar to 4,000-6,000) the entire wavelength range is observed simultaneously, while the high-resolution mode will cover three selected sub-regions simultaneously: one region with R similar to 8,000 near the Ca II triplet to measure stellar radial velocities, and two regions at R similar to 20,000 (one in each of the J- and H-bands), for precision measurements of chemical abundances.
|
|
| 9. |
- Yusuf, D, et al.
(författare)
-
The transcription factor encyclopedia
- 2012
-
Ingår i: Genome biology. - : Springer Science and Business Media LLC. - 1474-760X .- 1465-6906. ; 13:3, s. R24-
-
Tidskriftsartikel (refereegranskat)
|
|
| 10. |
- Schüpbach, S., et al.
(författare)
-
Greenland records of aerosol source and atmospheric lifetime changes from the Eemian to the Holocene
- 2018
-
Ingår i: Nature Communications. - : Springer Science and Business Media LLC. - 2041-1723. ; 9:1
-
Tidskriftsartikel (refereegranskat)abstract
- The Northern Hemisphere experienced dramatic changes during the last glacial, featuring vast ice sheets and abrupt climate events, while high northern latitudes during the last interglacial (Eemian) were warmer than today. Here we use high-resolution aerosol records from the Greenland NEEM ice core to reconstruct the environmental alterations in aerosol source regions accompanying these changes. Separating source and transport effects, we find strongly reduced terrestrial biogenic emissions during glacial times reflecting net loss of vegetated area in North America. Rapid climate changes during the glacial have little effect on terrestrial biogenic aerosol emissions. A strong increase in terrestrial dust emissions during the coldest intervals indicates higher aridity and dust storm activity in East Asian deserts. Glacial sea salt aerosol emissions in the North Atlantic region increase only moderately (50%), likely due to sea ice expansion. Lower aerosol concentrations in Eemian ice compared to the Holocene are mainly due to shortened atmospheric residence time, while emissions changed little.
|
|
| 11. |
|
|
| 12. |
|
|
| 13. |
|
|
| 14. |
- Hindy, George, et al.
(författare)
-
Increased soluble urokinase plasminogen activator levels modulate monocyte function to promote atherosclerosis
- 2022
-
Ingår i: Journal of Clinical Investigation. - 0021-9738. ; 132:24, s. 1-14
-
Tidskriftsartikel (refereegranskat)abstract
- People with kidney disease are disproportionately affected by atherosclerosis for unclear reasons. Soluble urokinase plasminogen activator receptor (suPAR) is an immune-derived mediator of kidney disease, levels of which are strongly associated with cardiovascular outcomes. We assessed suPAR’s pathogenic involvement in atherosclerosis using epidemiologic, genetic, and experimental approaches. We found serum suPAR levels to be predictive of coronary artery calcification and cardiovascular events in 5,406 participants without known coronary disease. In a genome-wide association meta-analysis including over 25,000 individuals, we identified a missense variant in the plasminogen activator, urokinase receptor (PLAUR) gene (rs4760), confirmed experimentally to lead to higher suPAR levels. Mendelian randomization analysis in the UK Biobank using rs4760 indicated a causal association between genetically predicted suPAR levels and atherosclerotic phenotypes. In an experimental model of atherosclerosis, proprotein convertase subtilisin/kexin–9 (Pcsk9) transfection in mice overexpressing suPAR (suPARTg) led to substantially increased atherosclerotic plaques with necrotic cores and macrophage infiltration compared with those in WT mice, despite similar cholesterol levels. Prior to induction of atherosclerosis, aortas of suPARTg mice excreted higher levels of CCL2 and had higher monocyte counts compared with WT aortas. Aortic and circulating suPARTg monocytes exhibited a proinflammatory profile and enhanced chemotaxis. These findings characterize suPAR as a pathogenic factor for atherosclerosis acting at least partially through modulation of monocyte function.
|
|
| 15. |
- Beaumont, Robin N, et al.
(författare)
-
Genome-wide association study of placental weight identifies distinct and shared genetic influences between placental and fetal growth.
- 2023
-
Ingår i: Nature genetics. - 1546-1718 .- 1061-4036. ; 55:11, s. 1807-19
-
Tidskriftsartikel (refereegranskat)abstract
- A well-functioning placenta is essential for fetal and maternal health throughout pregnancy. Using placental weight as a proxy for placental growth, we report genome-wide association analyses in the fetal (n=65,405), maternal (n=61,228) and paternal (n=52,392) genomes, yielding 40 independent association signals. Twenty-six signals are classified as fetal, four maternal and three fetal and maternal. A maternal parent-of-origin effect is seen near KCNQ1. Genetic correlation and colocalization analyses reveal overlap with birth weight genetics, but 12 loci are classified as predominantly or only affecting placental weight, with connections to placental development and morphology, and transport of antibodies and amino acids. Mendelian randomization analyses indicate that fetal genetically mediated higher placental weight is causally associated with preeclampsia risk and shorter gestational duration. Moreover, these analyses support the role of fetal insulin in regulating placental weight, providing a key link between fetal and placental growth.
|
|
| 16. |
|
|
| 17. |
|
|
| 18. |
- Eyerich, K, et al.
(författare)
-
IL-23 blockade with guselkumab potentially modifies psoriasis pathogenesis: rationale and study protocol of a phase 3b, randomised, double-blind, multicentre study in participants with moderate-to-severe plaque-type psoriasis (GUIDE)
- 2021
-
Ingår i: BMJ open. - : BMJ. - 2044-6055. ; 11:9, s. e049822-
-
Tidskriftsartikel (refereegranskat)abstract
- Guselkumab is an interleukin (IL)-23 pathway blocker with proven efficacy in patients with moderate-to-severe plaque psoriasis. Early intervention with guselkumab may result in changes to the clinical disease course versus later intervention.Methods and analysisHere we present the rationale and design of a phase 3b, randomised, double-blind, multicentre study (GUIDE), comparing treatment effects of guselkumab in patients with short (≤2 years) or longer (>2 years) duration of plaque-type psoriasis, measured from first appearance of psoriatic plaques. Participants achieving skin clearance (Psoriasis Area and Severity Index (PASI)=0) by week 20 and maintaining complete clearance at week 28 visit (‘super-responders’ (SRe)) will be randomised to continue approved maintenance dosing every 8 weeks (q8w) versus an investigational maintenance dosing interval of 16 weeks (q16w) until week 68. Primary endpoint: proportion of participants in the q8w vs q16w arms with absolute PASI <3 at week 68. Participants with PASI <3 at week 68 will be withdrawn from guselkumab treatment for up to 48 weeks. Participants not achieving SRe criteria (non-SRe) will remain in the study with q8w guselkumab dosing through week 68. Additional to serum samples obtained from all patients, skin biopsies and whole-blood samples will be taken from SRe and non-SRe participants at various time points in optional substudies. Analyses include: genetics; immunophenotyping (fluorescence-activated cell sorting); gene and protein expression profiling; immunohistology. By merging clinical endpoints with mechanistic findings, this study aims to elucidate how IL-23 blockade with guselkumab can modify the disease course by altering molecular and cellular drivers that cause relapse after treatment withdrawal, particularly among SRe.Ethics and disseminationApproval obtained from ethics committee Medical Council Hamburg, Germany (PVN5925). GUIDE is compliant with the Declaration of Helsinki.Trial registration numberRegistered at ClinicalTrials.gov (NCT03818035). All primary endpoint results (prespecified analyses) will be submitted to peer-reviewed, international journals within 18 months after primary completion date.
|
|
| 19. |
|
|
| 20. |
|
|
| 21. |
- Pilgaard, K., et al.
(författare)
-
The T allele of rs7903146 TCF7L2 is associated with impaired insulinotropic action of incretin hormones, reduced 24 h profiles of plasma insulin and glucagon, and increased hepatic glucose production in young healthy men
- 2009
-
Ingår i: Diabetologia. - : Springer Science and Business Media LLC. - 1432-0428 .- 0012-186X. ; 52:7, s. 1298-1307
-
Tidskriftsartikel (refereegranskat)abstract
- We studied the physiological, metabolic and hormonal mechanisms underlying the elevated risk of type 2 diabetes in carriers of TCF7L2 gene. We undertook genotyping of 81 healthy young Danish men for rs7903146 of TCF7L2 and carried out various beta cell tests including: 24 h glucose, insulin and glucagon profiles; OGTT; mixed meal test; IVGTT; hyperglycaemic clamp with co-infusion of glucagon-like peptide (GLP)-1 or glucose-dependent insulinotropic polypeptide (GIP); and a euglycaemic-hyperinsulinaemic clamp combined with glucose tracer infusion to study hepatic and peripheral insulin action. Carriers of the T allele were characterised by reduced 24 h insulin concentrations (p < 0.05) and reduced insulin secretion relative to glucose during a mixed meal test (beta index: p < 0.003), but not during an IVGTT. This was further supported by reduced late-phase insulinotropic action of GLP-1 (p = 0.03) and GIP (p = 0.07) during a 7 mmol/l hyperglycaemic clamp. Secretion of GLP-1 and GIP during the mixed meal test was normal. Despite elevated hepatic glucose production, carriers of the T allele had significantly reduced 24 h glucagon concentrations (p < 0.02) suggesting altered alpha cell function. Elevated hepatic glucose production and reduced insulinotropic effect of incretin hormones contribute to an increased risk of type 2 diabetes in carriers of the rs7903146 risk T allele of TCF7L2.
|
|
| 22. |
|
|
| 23. |
|
|
| 24. |
|
|
| 25. |
|
|
| 26. |
|
|
| 27. |
|
|
| 28. |
- Subhash, Santhilal, 1987, et al.
(författare)
-
Transcriptome-wide Profiling of Cerebral Cavernous Malformations Patients Reveal Important Long noncoding RNA molecular signatures : Long noncoding RNA molecular signatures in Cerebral Cavernous Malformations
- 2019
-
Ingår i: Scientific Reports. - : Springer Science and Business Media LLC. - 2045-2322. ; 9:1
-
Tidskriftsartikel (refereegranskat)abstract
- Cerebral cavernous malformations (CCMs) are low-flow vascular malformations in the brain associated with recurrent hemorrhage and seizures. The current treatment of CCMs relies solely on surgical intervention. Henceforth, alternative non-invasive therapies are urgently needed to help prevent subsequent hemorrhagic episodes. Long non-coding RNAs (lncRNAs) belong to the class of non-coding RNAs and are known to regulate gene transcription and involved in chromatin remodeling via various mechanism. Despite accumulating evidence demonstrating the role of lncRNAs in cerebrovascular disorders, their identification in CCMs pathology remains unknown. The objective of the current study was to identify lncRNAs associated with CCMs pathogenesis using patient cohorts having 10 CCM patients and 4 controls from brain. Executing next generation sequencing, we performed whole transcriptome sequencing (RNA-seq) analysis and identified 1,967 lncRNAs and 4,928 protein coding genes (PCGs) to be differentially expressed in CCMs patients. Among these, we selected top 6 differentially expressed lncRNAs each having significant correlative expression with more than 100 differentially expressed PCGs. The differential expression status of the top lncRNAs, SMIM25 and LBX2-AS1 in CCMs was further confirmed by qRT-PCR analysis. Additionally, gene set enrichment analysis of correlated PCGs revealed critical pathways related to vascular signaling and important biological processes relevant to CCMs pathophysiology. Here, by transcriptome-wide approach we demonstrate that lncRNAs are prevalent in CCMs disease and are likely to play critical roles in regulating important signaling pathways involved in the disease progression. We believe, that detailed future investigations on this set of identified lncRNAs can provide useful insights into the biology and, ultimately, contribute in preventing this debilitating disease.
|
|
| 29. |
- Teleki, A, et al.
(författare)
-
Flame-coating of titania particles with silica
- 2005
-
Ingår i: Journal of Materials Research. - Swiss Fed Inst Technol, Particle Technol Lab, Inst Proc Engn, Dept Mech & Proc Engn, CH-8092 Zurich, Switzerland. Swiss Fed Inst Technol, Dept Chem & Appl Biosci, Inorgan Chem Lab, CH-8093 Zurich, Switzerland.. - 0884-2914 .- 2044-5326. ; 20:5, s. 1336-1347
-
Tidskriftsartikel (refereegranskat)abstract
- Silica/titania composite particles were prepared by co-oxidation of titanium-tetra-isopropoxide and hexamethyldisiloxane in a co-flow diffusion flame reactor. The influence of precursor composition on product powder characteristics was studied by x-ray diffraction, nitrogen adsorption, electron microscopy, elemental mapping, and energy-dispersive x-ray analysis. The flame temperature was measured by Fourier transform infrared spectroscopy. The evolution of composite particle morphology from ramified agglomerates to spot- or fully coated particles was investigated by thermophoretic sampling and transmission/scanning electron microscopy. At 40-60 wt% TiO2, particles with segregated regions of silica and titania were formed, while at 80 wt% TiO2 rough silica coatings were obtained. Rapid flame-quenching with a critical flow nozzle at 5 cm above the burner nearly halved the product particle size, changed its crystallinity from pure anatase to mostly rutile and resulted in smooth silica coatings on particles containing 80 wt% TiO2.
|
|
| 30. |
- Tillett, W, et al.
(författare)
-
DYNAMICS OF NAIL PSORIASIS WITH GUSELKUMAB TREATMENT AND WITHDRAWAL IN ASSOCIATION WITH SKIN RESPONSE AND PATIENT-REPORTED OUTCOMES: A POST HOC ANALYSIS OF THE VOYAGE 2 PHASE 3 TRIAL
- 2022
-
Ingår i: ANNALS OF THE RHEUMATIC DISEASES. - : BMJ. - 0003-4967 .- 1468-2060. ; 81, s. 830-830
-
Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- Nail psoriasis can be difficult to treat, affects ~50% of patients with psoriasis and can involve the nail matrix (pitting, leukonychia) and/or nail bed (onycholysis, splinter haemorrhages). Evidence suggests nail psoriasis may be associated with risk of developing psoriatic arthritis, in particular distal interphalangeal joint erosion.1–3 Data to Week (Wk) 24 from VOYAGE 1 and 2, two Phase 3 clinical trials, indicate that the anti-interleukin-23 monoclonal antibody guselkumab (GUS) is more effective than placebo and as effective as adalimumab in treating nail psoriasis.4 Furthermore, GUS is also associated with maintained Psoriasis Area and Severity Index (PASI) following treatment withdrawal in VOYAGE 2; however, nail response is not as well understood in this context.5ObjectivesThis VOYAGE 2 post hoc analysis evaluated nail response and its association with skin response and patient-reported outcomes (PROs) in two groups, one experiencing GUS withdrawal and the other receiving continuous GUS.MethodsPatients had moderate-to-severe plaque psoriasis and nail psoriasis, were initially randomised to GUS, and achieved PASI 90 at Wk 28. Patients were then re-randomised to placebo (GUS withdrawal) or GUS every 8 wks (GUS continuation). Nail Psoriasis Severity Index (NAPSI; grading the most affected nail), fingernail Physician’s Global Assessment (f-PGA), PASI and Dermatology Life Quality Index (DLQI) are reported as observed at Wk 0, 16, 24 and 48.ResultsAmong 209 patients, NAPSI, f-PGA, PASI and DLQI showed similar trends in both groups until Wk 24. All endpoints improved from baseline; and at Wk 24, patients in the GUS withdrawal and GUS continuation groups achieved a mean NAPSI of 1.7 and 1.8 (nail matrix 1.0 and 1.0; nail bed 0.7 and 0.8); f-PGA 0.9 and 0.9; PASI 0.6 and 0.6; and DLQI 2.2 and 2.3, respectively (Table 1). Nail changes continued to follow skin trends through Wk 48 (Figure 1); with GUS withdrawal, worsening of PASI and DLQI was proportionally greater than that of NAPSI and f-PGA; with GUS continuation, PASI and DLQI remained fairly stable, and NAPSI and f-PGA continued to improve. Nails were numerically slower to respond to GUS initiation and withdrawal than skin, with a more pronounced delay for nail matrix vs nail bed. In patients who sustained a PASI 90 response at Wk 48, despite GUS withdrawal, a high level of nail response was also maintained.Table 1.NAPSI, f-PGA, PASI and DLQI through Wk 48 in GUS withdrawal and GUS continuation groupsWk 0Wk 16Wk 24Wk 28Wk 48GUS withdrawal*GUSRPlacebon97969696NAPSI5.0 (2.1)2.5 (1.9)1.7 (1.9)1.9 (2.1)Nail matrix2.7 (1.3)1.5 (1.3)1.0 (1.2)0.9 (1.3)Nail bed2.2 (1.2)0.9 (1.0)0.7 (1.0)1.0 (1.1)n98979797f-PGA2.5 (0.8)1.3 (0.9)0.9 (0.8)1.1 (1.0)n101101100100PASI23.1 (9.0)1.3 (2.7)0.6 (1.4)5.2 (6.1)n101101100100DLQI14.5 (6.1)2.8 (4.1)2.2 (3.6)7.0 (7.4)GUS continuationGUSRGUSn108106107105NAPSI4.4 (1.8)2.4 (2.2)1.8 (2.0)1.2 (1.6)Nail matrix2.5 (1.2)†1.4 (1.3)1.0 (1.2)0.7 (1.0)Nail bed1.9 (1.2)1.0 (1.1)0.8 (1.0)0.5 (0.8)n108106107105f-PGA2.4 (0.9)1.1 (0.9)0.9 (0.9)0.7 (0.8)n108108108106PASI22.6 (8.8)1.2 (2.1)0.6 (1.1)1.3 (3.5)n107108108104DLQI14.3 (6.4)2.9 (4.2)2.3 (4.0)1.8 (3.4)Data are mean (standard deviation). *n=10 reinitiated GUS upon loss of 50% of Wk 28 PASI 90(at n=1 Wk 36, n=2 Wk 40, n=7 Wk 44); †n=107; R, re-randomisation of PASI 90 responders.ConclusionGUS treatment through Wk 48 improved nail psoriasis, skin psoriasis and PROs. When GUS was withdrawn, loss of response was slower in nails vs skin. These findings support that nail outcomes follow skin outcome trends with GUS treatment and that nail outcomes should contribute to evaluation of treatment efficacy and disease progression.2,3,6References[1]Robert B. Dermatology 2010; 221 Suppl 1: 1–5;[2]Antony A et al. J Rheumatol 2019; 46: 1097–102.[3]Wilson F et al. Arthritis Rheum 2009; 61: 233–39;[4]Foley P et al. JAMA Dermatol 2018; 154: 676–83;[5]Conrad C et al. AAD 2021. P26573.[6]Conrad C et al. Dermatol Ther 2022; 12: 233–41.AcknowledgementsThis analysis was funded by Janssen and medical writing support was provided by OPEN Health Medical Communications.Disclosure of InterestsWilliam Tillett Speakers bureau: Abbvie, Amgen, Eli Lilly, Janssen, Novartis, Pfizer and UCB, Consultant of: Abbvie, Amgen, Eli Lilly, Janssen, Novartis, Pfizer and UCB, Grant/research support from: Abbvie, Amgen, Eli Lilly, Janssen, Novartis, Pfizer and UCB, Alexander Egeberg Speakers bureau: AbbVie, Almirall, Leo Pharma, Zuellig Pharma Ltd., Galápagos NV, Sun Pharmaceuticals, Samsung Bioepis Co., Ltd., Pfizer, Eli Lilly and Company, Novartis, Union Therapeutics, Galderma, Dermavant, UCB, Mylan, Bristol-Myers Squibb, and JanssenPharmaceuticals, Consultant of: AbbVie, Almirall, Leo Pharma, Zuellig Pharma Ltd., Galápagos NV, Sun Pharmaceuticals, Samsung Bioepis Co., Ltd., Pfizer, Eli Lilly and Company, Novartis, Union Therapeutics, Galderma, Dermavant, UCB, Mylan, Bristol-Myers Squibb, and JanssenPharmaceuticals, Grant/research support from: Pfizer, Eli Lilly, Novartis, Bristol-Myers Squibb, AbbVie, Janssen Pharmaceuticals, the Danish National Psoriasis Foundation, the Simon Spies Foundation, and the Kgl Hofbundtmager Aage Bang Foundation, Enikö Sonkoly Speakers bureau: AbbVie, Eli Lilly, UCB, Janssen, Novartis, Sanofi and LEO Pharma, Grant/research support from: Pfizer, Patricia Gorecki Employee of: Janssen, Anna Tjärnlund Employee of: Janssen, Jozefien Buyze Employee of: Janssen, Sven Wegner Employee of: Janssen, Dennis McGonagle Speakers bureau: Abbvie, BMS, Celgene, Janssen, Novartis, Lilly, UCB, Grant/research support from: Abbvie, BMS, Celgene, Janssen, Novartis, Lilly, UCB
|
|
| 31. |
|
|
| 32. |
- Tison, J.-L., et al.
(författare)
-
Retrieving the paleoclimatic signal from the deeper part of the EPICA Dome C ice core
- 2015
-
Ingår i: The Cryosphere. - : Copernicus GmbH. - 1994-0416 .- 1994-0424. ; 9:4, s. 1633-1648
-
Tidskriftsartikel (refereegranskat)abstract
- An important share of paleoclimatic information is buried within the lowermost layers of deep ice cores. Because improving our records further back in time is one of the main challenges in the near future, it is essential to judge how deep these records remain unaltered, since the proximity of the bedrock is likely to interfere both with the recorded temporal sequence and the ice properties. In this paper, we present a multiparametric study (delta D-delta O-18(ice), delta O-18(atm), total air content, CO2, CH4, N2O, dust, high-resolution chemistry, ice texture) of the bottom 60 m of the EPICA (European Project for Ice Coring in Antarctica) Dome C ice core from central Antarctica. These bottom layers were subdivided into two distinct facies: the lower 12 m showing visible solid inclusions (basal dispersed ice facies) and the upper 48 m, which we will refer to as the basal clean ice facies. Some of the data are consistent with a pristine paleoclimatic signal, others show clear anomalies It is demonstrated that neither large-scale bottom refreezing of subglacial water, nor mixing (be it internal or with a local basal end term from a previous/initial ice sheet configuration) can explain the observed bottom-ice properties. We focus on the high-resolution chemical profiles and on the available remote sensing data on the subglacial topography of the site to propose a mechanism by which relative stretching of the bottom-ice sheet layers is made possible, due to the progressively confining effect of subglacial valley sides. This stress field change, combined with bottom-ice temperature close to the pressure melting point, induces accelerated migration recrystallization, which results in spatial chemical sorting of the impurities, depending on their state (dissolved vs. solid) and if they are involved or not in salt formation. This chemical sorting effect is responsible for the progressive build-up of the visible solid aggregates that therefore mainly originate from within, and not from incorporation processes of debris from the ice sheet's substrate. We further discuss how the proposed mechanism is compatible with the other ice properties described. We conclude that the paleoclimatic signal is only marginally affected in terms of global ice properties at the bottom of EPICA Dome C, but that the timescale was considerably distorted by mechanical stretching of MIS20 due to the increasing influence of the subglacial topography, a process that might have started well above the bottom ice. A clear paleoclimatic signal can therefore not be inferred from the deeper part of the EPICA Dome C ice core. Our work suggests that the existence of a flat monotonic ice bedrock interface, extending for several times the ice thickness, would be a crucial factor in choosing a future oldest ice drilling location in Antarctica.
|
|
| 33. |
- Werner, Kirstin, et al.
(författare)
-
Arctic in Rapid Transition : Priorities for the future of marine and coastal research in the Arctic
- 2016
-
Ingår i: Polar Science. - : Elsevier BV. - 1873-9652 .- 1876-4428. ; 10:3, s. 364-373
-
Tidskriftsartikel (refereegranskat)abstract
- Understanding and responding to the rapidly occurring environmental changes in the Arctic over the past few decades require new approaches in science. This includes improved collaborations within the scientific community but also enhanced dialogue between scientists and societal stakeholders, especially with Arctic communities. As a contribution to the Third International Conference on Arctic Research Planning (ICARPIII), the Arctic in Rapid Transition (ART) network held an international workshop in France, in October 2014, in order to discuss high-priority requirements for future Arctic marine and coastal research from an early-career scientists (ECS) perspective. The discussion encompassed a variety of research fields, including topics of oceanographic conditions, sea-ice monitoring, marine biodiversity, land-ocean interactions, and geological reconstructions, as well as law and governance issues. Participants of the workshop strongly agreed on the need to enhance interdisciplinarity in order to collect comprehensive knowledge about the modern and past Arctic Ocean's geo-ecological dynamics. Such knowledge enables improved predictions of Arctic developments and provides the basis for elaborate decision-making on future actions under plausible environmental and climate scenarios in the high northern latitudes. Priority research sheets resulting from the workshop's discussions were distributed during the ICARPIII meetings in April 2015 in Japan, and are publicly available online. (C) 2016 Elsevier B.V. and NIPR. All rights reserved.
|
|
| 34. |
- Wolff, E. W., et al.
(författare)
-
Changes in environment over the last 800,000 years from chemical analysis of the EPICA Dome C ice core
- 2010
-
Ingår i: Quaternary Science Reviews. - : Elsevier BV. - 0277-3791 .- 1873-457X. ; 29:1-2, s. 285-295
-
Tidskriftsartikel (refereegranskat)abstract
- The EPICA ice core from Dome C extends 3259 m in depth, and encompasses 800 ka of datable and sequential ice. Numerous chemical species have been measured along the length of the cores. Here we concentrate on interpreting the main low-resolution patterns of major ions. We extend the published record for non-sea-salt calcium, sea-salt sodium and non-sea-salt sulfate flux to 800 ka. The non-sea-salt calcium record confirms that terrestrial dust originating from South America closely mirrored Antarctic climate, both at orbital and millennial timescales. A major cause of the main trends is most likely climate in southern South America, which could be sensitive to subtle changes in atmospheric circulation. Sea-salt sodium also follows temperature, but With a threshold at low temperature. We re-examine the use of sodium as a sea ice proxy, concluding that it is probably reflecting extent, with high salt concentrations reflecting larger ice extents. With this interpretation, the sodium flux record indicates low ice extent operating as an amplifier in warm interglacials. Non-sea-salt sulfate flux is almost constant along the core, confirming the lack of change in marine productivity (for sulfur-producing organisms) in the areas of the Southern Ocean contributing to the flux at Dome C. For the first time we also present long records of reversible species such as nitrate and chloride, and show that the pattern of post-depositional losses described for shallower ice is maintained in older ice. It appears possible to use these concentrations to constrain snow accumulation rates in interglacial ice at this site, and the results suggest a possible correction to accumulation rates in one early interglacial. Taken together the chemistry records offer a number of constraints on the way the Earth system combined to give the major climate fluctuations of the late Quaternary period.
|
|
