| 2. |
- Boyajian, T., et al.
(författare)
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Stellar diameters and temperatures - VI. High angular resolution measurements of the transiting exoplanet host stars HD 189733 and HD 209458 and implications for models of cool dwarfs
- 2015
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Ingår i: Monthly notices of the Royal Astronomical Society. - : Oxford University Press (OUP). - 0035-8711 .- 1365-2966. ; 447:1, s. 846-857
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Tidskriftsartikel (refereegranskat)abstract
- We present direct radii measurements of the well-known transiting exoplanet host stars HD 189733 and HD 209458 using the CHARA Array interferometer. We find the limb-darkened angular diameters to be thetaLD = 0.3848 +/- 0.0055 and 0.2254 +/- 0.0072 milliarcsec for HD 189733 and HD 209458, respectively. HD 189733 and HD 209458 are currently the only two transiting exoplanet systems where detection of the respective planetary companion's orbital motion from high resolution spectroscopy has revealed absolute masses for both star and planet. We use our new measurements together with the orbital information from radial velocity and photometric time series data, Hipparcos distances, and newly measured bolometric fluxes to determine the stellar effective temperatures (Teff = 4875 +/- 43, 6093 +/- 103 K), stellar linear radii (R* = 0.805 +/- 0.016, 1.203 +/- 0.061 Rsun), mean stellar densities (rho* = 1.62 +/- 0.11, 0.58 +/- 0.14 rhosun), planetary radii (Rp = 1.216 +/- 0.024, 1.451 +/- 0.074 RJup), and mean planetary densities (rhop = 0.605 +/- 0.029, 0.196 +/- 0.033 rhoJup) for HD 189733 b and HD 209458 b, respectively. The stellar parameters for HD 209458, a F9 dwarf, are consistent with indirect estimates derived from spectroscopic and evolutionary modeling. However, we find that models are unable to reproduce the observational results for the K2 dwarf, HD 189733. We show that, for stellar evolutionary models to match the observed stellar properties of HD 189733, adjustments lowering the solar-calibrated mixing length parameter from 1.83 to 1.34 need to be employed.
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| 3. |
- Lodge, J. P., et al.
(författare)
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Efficacy and safety of repeated perioperative doses of recombinant factor VIIa in liver transplantation
- 2005
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Ingår i: Liver transplantation. - : Ovid Technologies (Wolters Kluwer Health). - 1527-6465 .- 1527-6473. ; 11:8, s. 973-9
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Tidskriftsartikel (refereegranskat)abstract
- Patients undergoing orthotopic liver transplantation (OLT) have excessive blood loss during surgery that requires blood transfusions, leading to increased postoperative morbidity and mortality. We studied the efficacy and safety of activated recombinant factor VII (rFVIIa) in reducing transfusion requirements in OLT. This multicenter, randomized, double-blind, placebo-controlled trial enrolled patients undergoing OLT because of cirrhosis (Child-Turcotte-Pugh class B or C). Patients received a repeated intravenous bolus regimen of rFVIIa 60 or 120 microg/kg or placebo. The primary efficacy endpoint was the total number of red blood cell (RBC) units transfused during the perioperative period. A total of 182 patients were analyzed for efficacy and 183 for safety. No significant effect of rFVIIa was observed on the number of RBC units transfused or intraoperative blood loss compared with the placebo group. A significantly higher number of patients in the rFVIIa study groups avoided RBC transfusion. Administration of rFVIIa but not placebo restored the preoperative prolonged prothrombin time to normal value during surgery. Patients receiving rFVIIa and placebo did not experience a significant difference in rate of thromboembolic events. Additionally, there was no statistically significant effect of rFVIIa treatment on hospitalization rate, total surgery time, and the proportion of patients undergoing retransplantation. In conclusion, use of rFVIIa during OLT significantly reduced the number of patients requiring RBC transfusion. There was no increase in thromboembolic events with rFVIIa administration compared with placebo.
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