Upper limit for Poisson variable incorporating systematic uncertainties by Bayesian approach

2007 ◽  
Vol 578 (1) ◽  
pp. 322-328 ◽  
Author(s):  
Yongsheng Zhu
Keyword(s):  
Bayesian Approach ◽  
Upper Limit ◽  
Systematic Uncertainties ◽  
Poisson Variable

scholarly journals Limits on a stochastic background of gravitational waves

1996 ◽  
Vol 160 ◽  
pp. 129-130
Author(s):  
M. P. McHugh ◽  
G. Zalamansky ◽  
F. Vernotte ◽  
E. Lantz
Keyword(s):  
Energy Density ◽  
Bayesian Approach ◽  
Measurement Noise ◽  
Frequency Interval ◽  
Previous Knowledge ◽  
Upper Limit ◽  
Stochastic Background ◽  
Logarithmic Frequency ◽  
Gravitational Wave Background ◽  
Sufficient Strength

A gravitational wave background (GWB) of sufficient strength, characterized by Ω, the energy density per logarithmic frequency interval in units of the closure density, would introduce timing residuals in the most stable millisecond pulsars. For a description pertaining to the observations of PSR’s 1937+21 and 1855+09 see Kaspi, Taylor and Ryba (1994), hereafter KTR, and references therein. Thorsett and Dewey (1996, see also this volume) present a method for placing a statistical upper limit on Ω. Their method however, cannot correctly account for the presence of a known level of white measurement noise in the timing residuals. We use a Bayesian approach which can best account for this white noise along with our lack of previous knowledge on the parameter Ω (McHugh, Zalamansky, Vernotte and Lantz, submitted).

scholarly journals On the red supergiant problem

2020 ◽  
Vol 493 (4) ◽  
pp. 4945-4949 ◽  
Author(s):  
C S Kochanek
Keyword(s):  
Monte Carlo ◽  
Monte Carlo Simulations ◽  
Bayesian Approach ◽  
Mass Range ◽  
Mass Function ◽  
Initial Mass Function ◽  
Initial Mass ◽  
Maximum Mass ◽  
Upper Limit

ABSTRACT We examine the problem of estimating the mass range corresponding to the observed red supergiant (RSG) progenitors of Type IIP supernovae. Using Monte Carlo simulations designed to reproduce the properties of the observations, we find that the approach of Davies & Beasor significantly overestimates the maximum mass, yielding an upper limit of Mh/M⊙ = 20.5 ± 2.6 for an input population with Mh/M⊙ = 18. Our preferred Bayesian approach does better, with Mh/M⊙ = 18.6 ± 2.1 for the same input populations, but also tends to overestimate Mh. For the actual progenitor sample and a Salpeter initial mass function, we find $M_{\rm h}/\mathrm{M}_\odot = 19.01_{-2.04}^{+4.04}$ for the Eldridge & Tout mass–luminosity relation used by Smartt and Davies & Beasor, and $M_{\rm h}/\mathrm{M}_\odot = 21.28_{-2.28}^{+4.52}$ for the Sukhbold, Woosley & Heger mass–luminosity relation. Based on the Monte Carlo simulations, we estimate that these are overestimated by $(3.3\pm 0.8)\, \mathrm{M}_\odot$. The red supergiant problem remains.

Graves'-Basedow disease in pregnancy

2015 ◽  
Vol 54 (03) ◽  
pp. 106-111 ◽  
Author(s):  
S. L. Andersen ◽  
P. Laurberg
Keyword(s):  
Side Effects ◽  
Birth Defects ◽  
Thyroid Dysfunction ◽  
National Study ◽  
Antithyroid Drugs ◽  
Upper Limit ◽  
Special Concern ◽  
Maternal Thyroid ◽  
Toxic Reactions ◽  
Serum Tsh

SummaryThyroid hormones are essential development factors and maternal thyroid dysfunction may cause pregnancy complications and diseases in the fetus/child. In the present review we discuss new data on the incidence of Graves'-Basedow disease (GBD) in and around pregnancy, and how hyperthyroidism may affect the risk of spontaneous abortion and stillbirth.A special concern in pregnant women is the potential side effects from the use of antithyroid drugs (ATDs). One type of side effects is the allergic/toxic reactions to the drugs, which seem to be similar in and outside pregnancy, and another is that ATDs tend to over treat the fetus when the mother with GBD is made euthyroid. To avoid fetal hypothyroidism, the lowest possible ATD dose should be used to keep maternal thyroid function at the upper limit of normality with low serum TSH. Birth defects after the use of methimazole (MMI) (or its prodrug carbimazole) have been considered to be very rare, and no risk has previously been associated with the use of propylthiouracil (PTU). However, a recent Danish national study found that 1/30 of children exposed to MMI in early pregnancy had birth defects associated with this, and many defects were severe. PTU exposure was associated with defects in 1/40, and these defects were less severe. Proposals are given on how to reduce the risk of ATD associated birth defects.

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