| 1. |
- Smiljanic, R., et al.
(författare)
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The Gaia-ESO Survey: The analysis of high-resolution UVES spectra of FGK-type stars
- 2014
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Ingår i: Astronomy & Astrophysics. - : EDP Sciences. - 0004-6361 .- 1432-0746. ; 570
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Tidskriftsartikel (refereegranskat)abstract
- Context. The ongoing Gaia-ESO Public Spectroscopic Survey is using FLAMES at the VLT to obtain high-quality medium-resolution Giraffe spectra for about 10(5) stars and high-resolution UVES spectra for about 5000 stars. With UVES, the Survey has already observed 1447 FGK-type stars. Aims. These UVES spectra are analyzed in parallel by several state-of-the-art methodologies. Our aim is to present how these analyses were implemented, to discuss their results, and to describe how a final recommended parameter scale is defined. We also discuss the precision (method-to-method dispersion) and accuracy (biases with respect to the reference values) of the final parameters. These results are part of the Gaia-ESO second internal release and will be part of its first public release of advanced data products. Methods. The final parameter scale is tied to the scale defined by the Gaia benchmark stars, a set of stars with fundamental atmospheric parameters. In addition, a set of open and globular clusters is used to evaluate the physical soundness of the results. Each of the implemented methodologies is judged against the benchmark stars to define weights in three different regions of the parameter space. The final recommended results are the weighted medians of those from the individual methods. Results. The recommended results successfully reproduce the atmospheric parameters of the benchmark stars and the expected T-eff-log g relation of the calibrating clusters. Atmospheric parameters and abundances have been determined for 1301 FGK-type stars observed with UVES. The median of the method-to-method dispersion of the atmospheric parameters is 55K for T-eff, 0.13dex for log g and 0.07 dex for [Fe/H]. Systematic biases are estimated to be between 50-100 K for T-eff, 0.10-0.25 dex for log g and 0.05-0.10 dex for [Fe/H]. Abundances for 24 elements were derived: C, N, O, Na, Mg, Al, Si, Ca, Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Y, Zr, Mo, Ba, Nd, and Eu. The typical method-to-method dispersion of the abundances varies between 0.10 and 0.20 dex. Conclusions. The Gaia-ESO sample of high-resolution spectra of FGK-type stars will be among the largest of its kind analyzed in a homogeneous way. The extensive list of elemental abundances derived in these stars will enable significant advances in the areas of stellar evolution and Milky Way formation and evolution.
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| 2. |
- Jofre, P., et al.
(författare)
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Gaia FGK benchmark stars : Metallicity
- 2014
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Ingår i: Astronomy and Astrophysics. - : EDP Sciences. - 0004-6361 .- 1432-0746. ; 564, s. A133-
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Tidskriftsartikel (refereegranskat)abstract
- Context. To calibrate automatic pipelines that determine atmospheric parameters of stars, one needs a sample of stars, or "benchmark stars", with well-defined parameters to be used as a reference. Aims. We provide detailed documentation of the iron abundance determination of the 34 FGK-type benchmark stars that are selected to be the pillars for calibration of the one billion Gaia stars. They cover a wide range of temperatures, surface gravities, and metallicities. Methods. Up to seven different methods were used to analyze an observed spectral library of high resolutions and high signal-to-noise ratios. The metallicity was determined by assuming a value of effective temperature and surface gravity obtained from fundamental relations; that is, these parameters were known a priori and independently from the spectra. Results. We present a set of metallicity values obtained in a homogeneous way for our sample of benchmark stars. In addition to this value, we provide detailed documentation of the associated uncertainties.Finally, we report a value of the metallicity of the cool giant psi Phe for the first time.
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| 3. |
- Bergemann, M., et al.
(författare)
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The Gaia-ESO Survey : radial metallicity gradients and age-metallicity relation of stars in the Milky Way disk
- 2014
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Ingår i: Astronomy and Astrophysics. - : EDP Sciences. - 0004-6361 .- 1432-0746. ; 565, s. A89-
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Tidskriftsartikel (refereegranskat)abstract
- We study the relationship between age, metallicity, and alpha-enhancement of FGK stars in the Galactic disk. The results are based upon the analysis of high-resolution UVES spectra from the Gaia-ESO large stellar survey. We explore the limitations of the observed dataset, i.e. the accuracy of stellar parameters and the selection effects that are caused by the photometric target preselection. We find that the colour and magnitude cuts in the survey suppress old metal-rich stars and young metal-poor stars. This suppression may be as high as 97% in some regions of the age-metallicity relationship. The dataset consists of 144 stars with a wide range of ages from 0.5 Gyr to 13.5 Gyr, Galactocentric distances from 6 kpc to 9.5 kpc, and vertical distances from the plane 0 < vertical bar Z vertical bar < 1.5 kpc. On this basis, we find that i) the observed age-metallicity relation is nearly flat in the range of ages between 0 Gyr and 8 Gyr; ii) at ages older than 9 Gyr, we see a decrease in [Fe/H] and a clear absence of metal-rich stars; this cannot be explained by the survey selection functions; iii) there is a significant scatter of [Fe/H] at any age; and iv) [Mg/Fe] increases with age, but the dispersion of [Mg/Fe] at ages > 9 Gyr is not as small as advocated by some other studies. In agreement with earlier work, we find that radial abundance gradients change as a function of vertical distance from the plane. The [Mg/Fe] gradient steepens and becomes negative. In addition, we show that the inner disk is not only more alpha-rich compared to the outer disk, but also older, as traced independently by the ages and Mg abundances of stars.
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| 4. |
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| 5. |
- Barenius, B, et al.
(författare)
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Quality of life and clinical outcome after anterior cruciate ligament reconstruction using patellar tendon graft or quadrupled semitendinosus graft: an 8-year follow-up of a randomized controlled trial
- 2010
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Ingår i: The American journal of sports medicine. - : SAGE Publications. - 1552-3365 .- 0363-5465. ; 38:8, s. 1533-1541
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Tidskriftsartikel (refereegranskat)abstract
- Background: Randomized controlled trials after anterior cruciate ligament reconstructions with long-term follow-up including assessment of health-related quality of life are rare.Purpose: To compare clinical outcome and health-related quality of life 8 years after anterior cruciate ligament reconstruction using 2 types of graft.Study Design: Randomized controlled trial; Level of evidence, 1.Methods: Long-term follow-up of 164 patients with anterior cruciate ligament injury randomized to arthroscopic reconstruction with a quadrupled semitendinosus graft or a bone–patellar tendon–bone graft was undertaken. After a mean 8 years, 153 patients were available for follow-up, including instrumented laxity, 1-legged hop test, a knee-walking test, and assessment with International Knee Documentation Committee, Lysholm, Tegner, and patellofemoral pain score. Health-related quality of life was assessed with Knee Osteoarthritis Outcome Score and Short Form–36.Results: Patients in both graft groups retained the same stability, knee function, and health-related quality of life. The patellofemoral pain score was similar for both groups; the bone–patellar tendon–bone group had more donor site morbidity from kneeling and knee walking. In the bone–patellar tendon–bone group, 19 patients had no kneeling problems, 23 slight problems, 31 moderate problems, and 5 unable to kneel. Corresponding figures for the semitendinosus group were 25, 32, 16, and 2 ( P < .001). Patients with early reconstructions (<5 months) had a lower risk for meniscal injuries (37%) than did later reconstructed (62%, P = .008). Health-related quality of life regarding physical functioning in Short Form–36 was better for the early-reconstructed patients than for the later reconstructed (92 vs 85; P = .014). Patients without medial meniscal surgery had higher Knee Osteoarthritis Outcome Scores for all subscales than did patients with medial meniscal surgery, with most significant difference for sport and recreation (63 vs 75, P = .008).Conclusion: In the long term, the semitendinosus graft provided similar stability, knee function, and health-related quality of life but with less kneeling morbidity than did the bone–patellar tendon–bone graft.
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| 6. |
- Barenius, B, et al.
(författare)
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Quality of life and clinical outcome after anterior cruciate ligament reconstruction using patellar tendon graft or quadrupled semitendinosus graft: an 8-year follow-up of a randomized controlled trial (vol 38, pg 1533, 2010)
- 2011
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Ingår i: AMERICAN JOURNAL OF SPORTS MEDICINE. - : SAGE Publications. - 0363-5465 .- 1552-3365. ; 39:4, s. NP6-NP6
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Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)abstract
- Barenius B, Nordlander M, Ponzer S, Tidermark J, Eriksson K. Quality of life and clinical outcome after anterior cruciate ligament reconstruction using patellar tendon graft or quadrupled semitendinosus graft: an 8-year follow-up of a randomized controlled trial. Am J Sports Med. 2010;38(8):1533-1541. (Original DOI: 10.1177/0363546510369549) In the above article, There is an error in Table 1 (page 1535). In the 3rd row of data, which shows gender distribution in the graft groups, the percentage for male distribution in the whole study population was depicted instead of the percentage of male distribution in the specified graft groups. The data for number of male patients in the groups are correct, and the error does not influence any of the other results.
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| 7. |
- Czaun, Miklos, et al.
(författare)
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An investigation of Cu(II) and Ni(II)-catalysed hydrolysis of (di)imines
- 2010
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Ingår i: Inorganica Chimica Acta. - : Elsevier BV. - 0020-1693. ; 363:12, s. 3102-3112
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Tidskriftsartikel (refereegranskat)abstract
- The reactions of six diimine ligands with Cu(II) and Ni(II) halide salts have been investigated. The diimine ligands were Ph2C=N(CH2)(n)NC=Ph-2 (n = 2 (Bz(2)en, 1a), 3 (Bz(2)pn, 1b), 4 (Bz2bn, 1c)), N, N'-bis-(2-tert-butylthio- 1-ylmethylenebenzene)-2,2'diamino-biphenyl (2), N,N'-bis-(2-chloro-1-ylmethylenebenzene)-1,3diaminobenzene (3) and N,N'-bis-(2-chloro-1-ylmethylenebenzene)-1,2-ethanediamine (4). Reactions of 1a-c, 2-4 with CuCl2 center dot 2H(2)O in dry ethanol at ambient temperature led to complete or partial hydrolysis of the diimine ligands to ultimately form copper diamine complexes. The non-hydrolyzed complexes of 1b and 1c, [Cu(L)Cl-2] (L = 1b, 1c), could be isolated when the reactions were carried out at low temperatures, and the half-hydrolyzed complex [Cu(Bzpn)Cl-2] could also be identified via X-ray crystallography. Similarly, reactions of 1a or 1b with NiCl2 center dot 6H(2)O or [NiBr2(dme)] led to rapid hydrolysis of the imines and Ni complexes containing half-hydrolyzed 1a (Bzen; [trans-[Ni(Bzen)(2)Br-2]) and 1b (Bzpn; [Ni(Bzpn) Br-2] could be isolated and identified via single crystal X-ray analysis. Kinetic studies were made of the hydrolyses of 1a, 1b in THF and 2 in acetone, in the presence of Cu(II), and of 1a in acetonitrile, in the presence of Ni(II). Activation parameters were determined for the latter reaction and for the copper-catalyzed hydrolysis of 2; the relatively large negative activation entropies clearly indicate rate-determining steps of an associative nature.
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| 8. |
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| 9. |
- Lisper, Björn, et al.
(författare)
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Timing constraints : Theory meets practice
- 2012
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Ingår i: Lecture Notes in Computer Science, vol. 7610. - Berlin, Heidelberg : Springer. - 9783642340314 ; , s. 78-79, s. 78-79
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Bokkapitel (refereegranskat)abstract
- Many embedded systems must satisfy timing requirements, which describe how these systems should behave with respect to timing. Such requirements must be dealt with throughout the system development process: from their initial specification, expressed at an abstract level, through the increasingly concrete layers, to the final implementation level. There is a growing awareness that this process needs support from languages, tools, and methodologies.
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| 10. |
- Malinkin, Sergey O., et al.
(författare)
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Novel pyrazolate-based copper(II) [2 x 2] grid complexes: Synthesis, structure and properties
- 2012
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Ingår i: Inorganica Chimica Acta. - : Elsevier BV. - 0020-1693. ; 392, s. 322-330
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Tidskriftsartikel (refereegranskat)abstract
- 5-Acetyl-substituted pyrazole-3-carboxylic acid (H2L) forms [2 x 2] grid-like tetranuclear Cu(II) complexes with four five-coordinated copper(II) ions bridged by pyrazolate groups. Despite a significant dissociation of [Cu4L4(H2O)(4)]center dot 4H(2)O (1) in aqueous solution(1), it was possible to substitute the coordinated water molecules by pyridine ligands or azide anions. The resulting tetranuclear complexes [Cu4L4Py4]center dot 2H(2)O (2) and Na-4[Cu4L4(N-3)(4)]center dot 7MeOH (3) were isolated and studied by X-ray diffraction analysis. In 2 and 3 the azide anions or pyridine molecules complete the distorted square-pyramidal coordination of each copper(II) center. Magnetic susceptibilities of the obtained compounds have been measured by SQUID techniques. Simulation of the data using a Heisenberg spin Hamiltonian approach showed that the bridges between the metals mediate weak intramolecular antiferromagnetic coupling (J in the range -13.3 to -17.1 cm (1)) and lead to a singlet ground state in all cases. (C) 2012 Elsevier B.V. All rights reserved.
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