36 research outputs found
A method to deconvolve stellar rotational velocities
Rotational speed is an important physical parameter of stars and knowing the
distribution of stellar rotational velocities is essential for the
understanding stellar evolution. However, it cannot be measured directly but
the convolution of the rotational speed and the sine of the inclination angle,
. We developed a method to deconvolve this inverse problem and obtain
the cumulative distribution function (CDF) for stellar rotational velocities
extending the work of Chandrasekhar & M\"unch (1950). This method is applied a)
to theoretical synthetic data recovering the original velocity distribution
with very small error; b) to a sample of about 12.000 field main--sequence
stars, corroborating that the velocity distribution function is
non--Maxwellian, but is better described by distributions based on the concept
of maximum entropy, such as Tsallis or Kaniadakis distribution functions. This
is a very robust and novel method that deconvolve the rotational velocity
cumulative distribution function from a sample of data in just one
single step without needing any convergence criteria.Comment: Accepted in A&
Analytical Solutions for Radiation-Driven Winds in Massive Stars. I: The Fast Regime
Accurate massloss rate estimates are crucial keys to study wind properties of
massive stars and test different evolutionary scenarios. From a theoretical
point of view, this implies to solve a complex set of differential equations in
which the radiation field and the hydrodynamics are strong coupled. The use of
analytical expression to represent the radiation force and the solution of the
equation of motion have many advantages over numerical integrations. Therefore,
in this work, we present an analytical expression as solution of the equation
of motion for radiation driven winds, in terms of the force multipliers
parameters. This analytical expression is obtained by employing the line
acceleration expression given by Villata (1992) and the methodology proposed by
Mueller and Vink (2008). On the other hand, we find useful relationships to
determine the parameters for the line acceleration given by Mueller and Vink
(2008) in terms of the force multiplier parameters.Comment: Accepted for publication in ApJ (2014 November 1) 27 pages 9 fig
Differences in the gas and dust distribution in the transitional disk of a sun-like young star, PDS 70
We present ALMA 0.87 mm continuum, HCO+ J=4--3 emission line, and CO J=3--2
emission line data of the disk of material around the young, Sun-like star PDS
70. These data reveal the existence of a possible two component transitional
disk system with a radial dust gap of 0."2 +/- 0."05, an azimuthal gap in the
HCO+ J=4--3 moment zero map, as well as two bridge-like features in the gas
data. Interestingly these features in the gas disk have no analogue in the dust
disk making them of particular interest. We modeled the dust disk using the
Monte Carlo radiative transfer code HOCHUNK3D (Whitney et al. 2013) using a two
disk components. We find that there is a radial gap that extends from 15-60 au
in all grain sizes which differs from previous work
Imaging the disc rim and a moving close-in companion candidate in the pre-transitional disc of V1247 Orionis
Context. V1247 Orionis harbours a pre-transitional disc with a partially cleared gap. Earlier interferometric and polarimetric observations revealed strong asymmetries both in the gap region and in the outer disc. The presence of a companion was inferred to explain these asymmetric structures and the ongoing disc clearing.We acknowledge support from an ERC Starting Grant
(Grant Agreement No. 639889), STFC Rutherford Fellowship (ST/J004030/1),
STFC Rutherford Grant (ST/K003445/1), Marie Sklodowska-Curie CIG grant
(Ref. 618910) and Philip Leverhulme Prize (PLP-2013-110). We additionally acknowledge support from NASA KPDA grants (JPL-1452321, 1474717,
1485953, 1496788)
Design and baseline characteristics of the finerenone in reducing cardiovascular mortality and morbidity in diabetic kidney disease trial
Background: Among people with diabetes, those with kidney disease have exceptionally high rates of cardiovascular (CV) morbidity and mortality and progression of their underlying kidney disease. Finerenone is a novel, nonsteroidal, selective mineralocorticoid receptor antagonist that has shown to reduce albuminuria in type 2 diabetes (T2D) patients with chronic kidney disease (CKD) while revealing only a low risk of hyperkalemia. However, the effect of finerenone on CV and renal outcomes has not yet been investigated in long-term trials.
Patients and Methods: The Finerenone in Reducing CV Mortality and Morbidity in Diabetic Kidney Disease (FIGARO-DKD) trial aims to assess the efficacy and safety of finerenone compared to placebo at reducing clinically important CV and renal outcomes in T2D patients with CKD. FIGARO-DKD is a randomized, double-blind, placebo-controlled, parallel-group, event-driven trial running in 47 countries with an expected duration of approximately 6 years. FIGARO-DKD randomized 7,437 patients with an estimated glomerular filtration rate >= 25 mL/min/1.73 m(2) and albuminuria (urinary albumin-to-creatinine ratio >= 30 to <= 5,000 mg/g). The study has at least 90% power to detect a 20% reduction in the risk of the primary outcome (overall two-sided significance level alpha = 0.05), the composite of time to first occurrence of CV death, nonfatal myocardial infarction, nonfatal stroke, or hospitalization for heart failure.
Conclusions: FIGARO-DKD will determine whether an optimally treated cohort of T2D patients with CKD at high risk of CV and renal events will experience cardiorenal benefits with the addition of finerenone to their treatment regimen.
Trial Registration: EudraCT number: 2015-000950-39; ClinicalTrials.gov identifier: NCT02545049
Abstracts from the 8th International Conference on cGMP Generators, Effectors and Therapeutic Implications
This work was supported by a restricted research grant of Bayer AG
Place de la grippe dans les infections respiratoires aiguës de l'enfant (étude rétrospective en Rhône-Alpes (2000-2004))
BESANCON-BU Médecine pharmacie (250562102) / SudocSudocFranceF
Studying the Magnetic Properties of Upper Main-sequence Stars with FORS1
We summarise the results of our recent magnetic field studies in upper main-sequence stars, which have exploited the spectropolarimetric capability of FORS1 at the VLT extensively