| 1. |
- Brzezinski, Juliusz, 1939, et al.
(författare)
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Smooth lattices over quadratic integers
- 2008
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Ingår i: Mathematische Zeitschrift. - : Springer Science and Business Media LLC. - 1432-1823 .- 0025-5874. ; 258:1, s. 161-184
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Tidskriftsartikel (refereegranskat)abstract
- We construct lattices with quadratic structure over the integers in quadratic number fields having the property that the rank of the quadratic structure is constant and equal to the rank of the lattice in all reductions modulo maximal ideals. We characterize the case in which such lattices are free. The construction gives a representative of the genus of such lattices as an orthogonal sum of "standard" pieces of ranks 1-4 and covers the case of the discriminant of the real quadratic number field congruent to 1 modulo 8 for which a general construction was not known. © 2007 Springer-Verlag.
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| 2. |
- Kiselman, Christer O., 1939-
(författare)
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How to best fold a triangle
- 2017
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Ingår i: Mathematische Semesterberichte. - : Springer Science and Business Media LLC. - 0720-728X .- 1432-1815. ; 65:1, s. 65-89
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Tidskriftsartikel (refereegranskat)abstract
- We fold a triangle once along a straight line and study how small the area of the folded figure can be. It can always be as small as the fraction 2 minus the square root of 2 of the area of the original triangle. This is best possible: For every positive number q less than 2 minus the square root of 2 there are triangles that cannot be folded better than the fraction q.
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| 3. |
- Kiselman, Christer Oscar, Guest Professor, 1939-, et al.
(författare)
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Existence of continuous right inverses to linear mappings in finite-dimensional geometry
- 2021
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Ingår i: Mathematische Semesterberichte. - : Springer Science and Business Media LLC. - 0720-728X .- 1432-1815. ; 68, s. 55-68
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Tidskriftsartikel (refereegranskat)abstract
- A linear mapping of a compact convex subset of a finite-dimensional vector space always possesses a right inverse, but may lack a continuous right inverse, even if the set is smoothly bounded. Examples showing this are given, as well as conditions guaranteeing the existence of a continuous right inverse.
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| 4. |
- Biver, N., et al.
(författare)
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Isotopic ratios of H, C, N, O, and S in comets C/2012 F6 (Lemmon) and C/2014 Q2 (Lovejoy)
- 2016
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Ingår i: Astronomy and Astrophysics. - : EDP Sciences. - 0004-6361 .- 1432-0746. ; 589, s. Art. no. A78-
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Tidskriftsartikel (refereegranskat)abstract
- The apparition of bright comets C/2012 F6 (Lemmon) and C/2014 Q2 (Lovejoy) in March-April 2013 and January 2015, combined with the improved observational capabilities of submillimeter facilities, offered an opportunity to carry out sensitive compositional and isotopic studies of the volatiles in their coma. We observed comet Lovejoy with the IRAM 30 m telescope between 13 and 26 January 2015, and with the Odin submillimeter space observatory on 29 January-3 February 2015. We detected 22 molecules and several isotopologues. The (H2O)-O-16 and (H2O)-O-18 production rates measured with Odin follow a periodic pattern with a period of 0.94 days and an amplitude of similar to 25%. The inferred isotope ratios in comet Lovejoy are O-16/O-18 = 499 +/- 24 and D/H = 1.4 +/- 0.4 x 10(-4) in water, S-32/S-34 = 24.7 +/- 3.5 in CS, all compatible with terrestrial values. The ratio C-12/C-13 = 109 +/- 14 in HCN is marginally higher than terrestrial and N-14/N-15 = 145 +/- 12 in HCN is half the Earth ratio. Several upper limits for D/H or C-12/C-13 in other molecules are reported. From our observation of HDO in comet C/2014 Q2 (Lovejoy), we report the first D/H ratio in an Oort Cloud comet that is not larger than the terrestrial value. On the other hand, the observation of the same HDO line in the other Oort-cloud comet, C/2012 F6 (Lemmon), suggests a D/H value four times higher. Given the previous measurements of D/H in cometary water, this illustrates that a diversity in the D/H ratio and in the chemical composition, is present even within the same dynamical group of comets, suggesting that current dynamical groups contain comets formed at very different places or times in the early solar system.
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| 5. |
- Biver, N., et al.
(författare)
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Periodic variation in the water production of comet C/2001 Q4 (NEAT) observed with the Odin satellite
- 2009
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Ingår i: Astronomy and Astrophysics. - 0004-6361 .- 1432-0746. ; 501:1, s. 359-366
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Tidskriftsartikel (refereegranskat)abstract
- Context: Comet C/2001 Q4 (NEAT) was extensively studied with the 1.1-m submillimetre telescope of the Odin satellite. The H2O line at 557 GHz was regularly observed from 6 March to 16 May 2004 and nearly continuously monitored during 3 periods between 26 April and 2 May 2004. Aims: This last set of data shows periodic variations in the line intensity, and we looked for characterising the long- and short-term behaviour of this comet. Methods: We used the variance ratio method and χ2 minimization to find the period of variation in the water production rate and simulations to infer its amplitude at the nucleus surface. Results: A 40% periodic variation in the water production rate is measured with a period of 0.816±0.004 day (19.58±0.1 h). The comet also exhibits a seasonal effect with a mean peak of outgassing around 2.7×1029 molec. s-1 taking place about 18 days before perihelion.
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| 6. |
- Bjerkeli, Per, 1977, et al.
(författare)
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Odin observations of water in molecular outflows and shocks
- 2009
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Ingår i: Astronomy and Astrophysics. - : EDP Sciences. - 0004-6361 .- 1432-0746. ; 507:3, s. 1455-1466
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Tidskriftsartikel (refereegranskat)abstract
- Aims: We investigate the ortho-water abundance in outflows and shocks in order to improve our knowledge of shock chemistry and of the physics behind molecular outflows.Methods: We used the Odin space observatory to observe the H2O(110-101) line. We obtain strip maps and single pointings of 13 outflows and two supernova remnants where we report detections for eight sources. We used RADEX to compute the beam averaged abundances of o-H2O relative to H2. In the case of non-detection, we derive upper limits on the abundance.Results: Observations of CO emission from the literature show that the volume density of H2 can vary to a large extent, a parameter that puts severe uncertainties on the derived abundances. Our analysis shows a wide range of abundances reflecting the degree to which shock chemistry affects the formation and destruction of water. We also compare our results with recent results from the SWAS team.Conclusions: Elevated abundances of ortho-water are found in several sources. The abundance reaches values as high as what would be expected from a theoretical C-type shock where all oxygen, not in the form of CO, is converted to water. However, the high abundances we derive could also be due to the low densities (derived from CO observations) that we assume. The water emission may in reality stem from high density regions much smaller than the Odin beam. We do not find any relationship between the abundance and the mass loss rate. On the other hand, there is a relation between the derived water abundance and the observed maximum outflow velocity.Odin is a Swedish-led satellite project funded jointly by the Swedish National Space Board (SNSB), the Canadian Space Agency (CSA), the National Technology Agency of Finland (Tekes) and Centre National d'Étude Spatiale (CNES).The Swedish ESO Submillimetre Telescope (SEST) located at La Silla, Chile was funded by the Swedish Research Council (VR) and the European Southern Observatory. It was decommissioned in 2003. Appendix B is only available in electronic form at http://www.aanda.org
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| 7. |
- Blomsterwall, Elisabeth, et al.
(författare)
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Postural function and subjective eye level in patients with idiopathic normal pressure hydrocephalus.
- 2011
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Ingår i: Journal of neurology. - : Springer Science and Business Media LLC. - 1432-1459 .- 0340-5354. ; 258:7, s. 1341-6
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Tidskriftsartikel (refereegranskat)abstract
- Disturbance of posture is a frequent indication of idiopathic normal pressure hydrocephalus (iNPH) and is characterised by an increased sway in the frontal and sagittal planes. Further, iNPH patients with increased backward sway are known to have a defective perception of the subjective visual vertical (SVV), with the upper portion of an articulated rod tilted towards themselves. The objective of the present study was to compare subjective eye level (SEL) with actual eye level (EL) and compare this data with SVV and postural function. Twenty iNPH patients and ten normal controls estimated SEL by placing an adjustable horizontal line at EL. Sway pattern and SVV were also examined as previously described. The patients presented larger errors on downward as compared to upward line adjustments; all patients also presented a SVV tilted towards them. The patients swayed more in the sagittal than in the frontal plane at a higher speed than the normal controls, and they were relatively less helped by their vision. This is in accordance with the tendency to fall backwards seen in many iNPH patients. iNPH patients have a tendency to place SEL higher than EL and this, together with examination of SVV and sway pattern, suggests defective internal processing of gravicentric information.
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| 8. |
- Dellve, Lotta, 1965, et al.
(författare)
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Myofeedback training and intensive muscular strength training to decrease pain and improve work ability among female workers on long-term sick leave with neck pain: a randomized controlled trial
- 2011
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Ingår i: International archives of occupational and environmental health. - : Springer Science and Business Media LLC. - 1432-1246 .- 0340-0131. ; 84:3, s. 335-46
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Tidskriftsartikel (refereegranskat)abstract
- Abstract The theoretical framework is that muscle tension in the neck is related to insufficient muscular rest and is a risk factor for chronic pain and reduced work ability. Promoting muscle strength and muscle rest may increase work ability and reduce neck pain. Objectives To test whether myofeedback training or intensive strength training leads to decreased pain and increased work ability in women on long-term sick leave. Methods This is a randomized controlled trial of two 1-month interventions with myofeedback or muscular strength training in the home environment. Female human service organization workers (n = 60) on long-term (>60 days) sick leave and with chronic neck pain were followed with self-reported and laboratory-observed data of health, pain, muscular activation, and work ability, at baseline, immediately after the intervention and 3 months after baseline. Results For both intervention groups, pain was lowered over time compared with the control group. Decreased pain and muscular activity was associated with increased self-rated work ability and with laboratory-observed work ability at 3-month follow-up. Decreased pain was also associated with increased self-rated work ability at 1-month follow-up. Muscular strength training was associated with increased self-rated work ability and mental health. Myofeedback was associated with increased observed work ability and self- rated vitality. Conclusions The two interventions showed positive results, suggesting that they could be developed for use in health care practice to address pain and work ability. The intensive muscular strength training program, which is both easy to conduct at home and easy to coach, was associated with increased work ability.
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| 9. |
- Enerbäck, Charlotta, 1965, et al.
(författare)
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Stronger association with HLA-Cw6 than with corneodesmosin (S-gene) polymorphisms in Swedish psoriasis patients.
- 2000
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Ingår i: Archives of dermatological research. - : Springer Science and Business Media LLC. - 0340-3696 .- 1432-069X. ; 292:11, s. 525-30
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Tidskriftsartikel (refereegranskat)abstract
- Psoriasis vulgaris is strongly associated with certain human leukocyte antigens, especially in early onset. The purpose of this study was to study the HLA-Cw6 allele and its contribution to disease susceptibility in a set of 104 families with at least two affected siblings. A sequencing method was utilized to examine the two exons that build up the antigen binding site of the C locus receptor. DNA from patients homozygous for Cw6 based on haplotype information were sequenced. The results confirmed the identity of the Cw6 allele in affected individuals with the consensus sequence for Cw*0602. We screened the set of families for psoriasis patients homozygous for Cw6 and found 11 individuals with a mean age at onset of 16.1 years. The corresponding figure for the Cw6 heterozygotes was 18.45 years and for the Cw6-negatives 22.36 years. This is indicative of a gene dose effect. We performed a transmission disequilibrium test (TDT) on the Cw6 allele per se, used as a biallelic marker. The analysis resulted in a P-value of 5.3 x 10(-17) (t167/nt45). This greatly exceeds our previous results of a TDT in the region, including microsatellite markers and single nucleotide polymorphisms (SNPs) in the coding part of the S gene (corneodesmosin), which is a suggested candidate gene in the region. The maximum nonparametric linkage (NPL) value was also reached using HLA-C as a marker. We conclude that Cw6 is the allele which shows the highest degree of association with psoriasis in our set of families and we propose that it directly influences the age at onset of the disease rather than increasing the genetic load in accordance with a polygenic theory.
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| 10. |
- Frisk, U., et al.
(författare)
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The Odin satellite - I. Radiometer design and test
- 2003
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Ingår i: Astronomy and Astrophysics. - 0004-6361 .- 1432-0746. ; 402:3, s. L27-L34
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Tidskriftsartikel (refereegranskat)abstract
- The Sub-millimetre and Millimetre Radiometer (SMR) is the main instrument on the Swedish, Canadian, Finnish and French spacecraft Odin. It consists of a 1.1 metre diameter telescope with four tuneable heterodyne receivers covering the ranges 486-504 GHz and 541-581 GHz, and one fixed at 118.75 GHz together with backends that provide spectral resolution from 150 kHz to 1 MHz. This Letter describes the Odin radiometer, its operation and performance with the data processing and calibration described in Paper II.
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