| 1. |
- Swayne,, et al.
(författare)
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The EBLM project - VIII. First results for M-dwarf mass, radius, and effective temperature measurements using CHEOPS light curves
- 2021
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Ingår i: Monthly Notices of the Royal Astronomical Society. - : Oxford University Press (OUP). - 0035-8711 .- 1365-2966. ; 506:1, s. 306-322
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Tidskriftsartikel (refereegranskat)abstract
- The accuracy of theoretical mass, radius, and effective temperature values for M-dwarf stars is an active topic of debate. Differences between observed and theoretical values have raised the possibility that current theoretical stellar structure and evolution models are inaccurate towards the low-mass end of the main sequence. To explore this issue, we use the CHEOPS satellite to obtain high-precision light curves of eclipsing binaries with low-mass stellar companions. We use these light curves combined with the spectroscopic orbit for the solar-type companion to measure the mass, radius, and effective temperature of the M-dwarf star. Here, we present the analysis of three eclipsing binaries. We use the pycheops data analysis software to fit the observed transit and eclipse events of each system. Two of our systems were also observed by the TESS satellite - we similarly analyse these light curves for comparison. We find consistent results between CHEOPS and TESS, presenting three stellar radii and two stellar effective temperature values of low-mass stellar objects. These initial results from our on-going observing programme with CHEOPS show that we can expect to have similar to 24 new mass, radius, and effective temperature measurements for very low-mass stars within the next few years.
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| 2. |
- Wilson, Kathryn M., et al.
(författare)
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Validation of a food frequency questionnaire measurement of dietary acrylamide intake using hemoglobin adducts of acrylamide and glycidamide
- 2009
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Ingår i: Cancer Causes and Control. - : Springer Science and Business Media LLC. - 0957-5243 .- 1573-7225. ; 20:3, s. 269-278
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Tidskriftsartikel (refereegranskat)abstract
- OBJECTIVE: Acrylamide, a probable human carcinogen, is formed during high-heat cooking of many common foods. The validity of food frequency questionnaire (FFQ) measures of acrylamide intake has not been established. We assessed the validity of acrylamide intake calculated from an FFQ using a biomarker of acrylamide exposure. METHODS: We calculated acrylamide intake from an FFQ in the Nurses' Health Study II. We measured hemoglobin adducts of acrylamide and its metabolite, glycidamide, in a random sample of 342 women. Correlation and regression analyses were used to assess the relationship between acrylamide intakes and adducts. RESULTS: The correlation between acrylamide intake and the sum of acrylamide and glycidamide adducts was 0.31 (95% CI: 0.20-0.41), adjusted for laboratory batch, energy intake, and age. Further adjustment for BMI, alcohol intake, and correction for random within-person measurement error in adducts gave a correlation of 0.34 (CI: 0.23-0.45). The intraclass correlation coefficient for the sum of adducts was 0.77 in blood samples collected 1-3 years apart in a subset of 45 women. Intake of several foods significantly predicted adducts in multiple regression. CONCLUSIONS: Acrylamide intake and hemoglobin adducts of acrylamide and glycidamide were moderately correlated. Within-person consistency in adducts was high over time.
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