| 51. |
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| 52. |
- Lundqvist, Peter
(författare)
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The Flash Ionization of the Circumstellar Gas of SN 1987A
- 2007
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Ingår i: UPERNOVA 1987A: 20 YEARS AFTER: Supernovae and Gamma-Ray Bursters. - : AIP. - 9780735404489
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Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- The photons from the shock breakout of SN 1987A ionized the gas they encountered in less than a few hours. Twenty years later the recombining circumstellar gas is still glowing. Here we discuss what the analysis of this emission has revealed about the structure and properties of the circumstellar gas, as well as about the properties of the shock breakout.
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| 53. |
- Lundqvist, Peter
(författare)
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Vi behöver landsbygdsambassader
- 2009
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Ingår i: Aftonbladet. - 1103-9000. ; , s. 30-31
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Tidskriftsartikel (populärvet., debatt m.m.)
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| 54. |
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| 55. |
- Mattila, Seppo, et al.
(författare)
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Massive stars exploding in a He-rich circumstellar medium - III. SN 2006jc : infrared echoes from new and old dust in the progenitor CSM
- 2008
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Ingår i: Monthly Notices of the Royal Astronomical Society. - : Oxford University Press (OUP). - 0035-8711 .- 1365-2966. ; 389:1, s. 141-155
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Tidskriftsartikel (refereegranskat)abstract
- We present near- (NIR) and mid-infrared (MIR) photometric data of the Type Ibn supernova (SN) 2006jc obtained with the United Kingdom Infrared Telescope (UKIRT), the Gemini North Telescope and the Spitzer Space Telescope between days 86 and 493 post-explosion. We find that the IR behaviour of SN 2006jc can be explained as a combination of IR echoes from two manifestations of circumstellar material. The bulk of the NIR emission arises from an IR echo from newly condensed dust in a cool dense shell (CDS) produced by the interaction of the ejecta outward shock with a dense shell of circumstellar material ejected by the progenitor in a luminous blue variable (LBV)-like outburst about two years prior to the SN explosion. The CDS dust mass reaches a modest 3.0 × 10-4Msolar by day 230. While dust condensation within a CDS formed behind the ejecta inward shock has been proposed before for one event (SN 1998S), SN 2006jc is the first one showing evidence for dust condensation in a CDS formed behind the ejecta outward shock in the circumstellar material. At later epochs, a substantial and growing contribution to the IR fluxes arises from an IR echo from pre-existing dust in the progenitor wind. The mass of the pre-existing circumstellar medium (CSM) dust is at least ~8 × 10-3Msolar. This paper therefore adds to the evidence that mass-loss from the progenitors of core-collapse SNe could be a major source of dust in the Universe. However, yet again, we see no direct evidence that the explosion of an SN produces anything other than a very modest amount of dust.
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| 56. |
- Nyholm, Dag, et al.
(författare)
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Enteral Levodopa/Carbidopa infusion in advanced Parkinson disease : Long-term exposure
- 2008
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Ingår i: Clinical neuropharmacology. - 0362-5664 .- 1537-162X. ; 31:2, s. 63-73
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Tidskriftsartikel (refereegranskat)abstract
- Objectives: In patients with advanced Parkinson disease, levodopa/carbidopa formulated as a gel suspension (Duodopa) permits continuous delivery into the small intestine using a portable pump, resulting in less variability in levodopa concentrations and fewer motor fluctuations and dyskinesias than with oral levodopa administration. This is a retrospective analysis of the long-term clinical experience with this agent. Methods: All but 1 of the patients who had received enteral levodopa infusion treatment between January 1, 1991, and June 30, 2002, consented to a review of their hospital charts. Results: Of the 65 patients with initial testing of the treatment, 86% opted for continued treatment via percutaneous endoscopic gastrostomy or gastrojejunostomy. Total exposure to levodopa infusion was 216 patient-years (mean, 3.7 years). Maximum treatment duration was 10.7 years. Fifty-two patients were treated for 1 year or longer. The adverse effect profile of levodopa/carbidopa infusion was similar to that observed with oral administration of levodopa. Seven deaths occurred, all considered unrelated to the treatment. Intestinal tube problems, including dislocation of the intestinal tube to the stomach, were the most common technical problem, occurring in 69% of the patients during the first year. The optimal daily dose of levodopa decreased by an average of 5% during follow-up. Conclusions: The safety of enteral infusion of levodopa/ carbidopa formulated as a gel suspension was found acceptable. For most patients, the technical challenges posed by the enteral infusion system were offset by the improvement in motor fluctuations and dyskinesias offered by this technique.
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| 57. |
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| 58. |
- Rivinoja, Peter, et al.
(författare)
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Migration success and migration time of gastrically radio-tagged v. PIT-tagged adult Atlantic salmon
- 2006
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Ingår i: Journal of Fish Biology. - : Wiley. - 0022-1112 .- 1095-8649. ; 69:1, s. 304-311
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Tidskriftsartikel (refereegranskat)abstract
- Adult Atlantic salmon (55–116 cm total length) with PIT-tags (n= 318) and both PIT-tags and gastric radio-tags (n= 127) in a regulated river showed similar upstream migration success, yet radio-tagged fish migrated faster than fish with only PIT-tags. Regurgitation rate of radio-tags was 9%.
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| 59. |
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| 60. |
- Serafimovich, Natalia I., 1974-, et al.
(författare)
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Optical observations of the young supernova remnant SNR 0540-69.3 and its pulsar
- 2005
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Ingår i: Advances in Space Research. - : Elsevier BV. - 0273-1177 .- 1879-1948. ; 35:6, s. 1106-1111
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Tidskriftsartikel (refereegranskat)abstract
- We have used the ESO NTT/EMMI and VLT/FORS1 instruments to examine the LMC supernova remnant 0540-69.3 as well as its pulsar (PSR B0540-69) and pulsar-powered nebula in the optical range. Spectroscopic observations of the remnant covering the range of 3600 7350 Å centered on the pulsar produced results consistent with those of [Kirshner, R.P., Morse, J.A., Winkler, P.F., et al. The penultimate supernova in the Large Magellanic Cloud - SNR 0540-69.3. Astrophys.J. 342, 260 271, 1989.] but also revealed many new emission lines. The most important are [Ne III] λλ3869, 3967 and Balmer lines of hydrogen. In both the central part of the remnant, as well as in nearby H II regions, the [O III] temperature is higher than ˜2 × 104 K, but lower than previously estimated. For PSR B0540-69, previous optical data are mutually inconsistent: HST/FOS spectra indicate a significantly higher absolute flux and steeper spectral index than suggested by early time-resolved groundbased UBVRI photometry. We show that the HST and VLT spectroscopic data for the pulsar have ≳50% nebular contamination, and that this is the reason for the previous difference. Using HST/WFPC2 archival images obtained in various bands from the red part of the optical to the NUV range we have performed an accurate photometric study of the pulsar, and find that the spectral energy distribution of the pulsar emission has a negative slope with α=1.07-0.19+0.20. This is steeper than derived from previous UBVRI photometry, and also different from the almost flat spectrum of the Crab pulsar. We also estimate that the proper motion of the pulsar is 4.9 ± 2.3 mas year‑1, corresponding to a transverse velocity of 1190 ± 560 km s‑1, projected along the southern jet of the pulsar nebula.
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