Asteroseismic constraints on K giants make it possible to infer radii, masses and ages of tens of thousands of field stars. Tests against independent estimates of these properties are however scarce, ...especially in the metal-poor regime. Here, we report the detection of solar-like oscillations in 8 stars belonging to the red-giant branch and red-horizontal branch of the globular cluster M4. The detections were made in photometric observations from the K2 Mission during its Campaign 2. Making use of independent constraints on the distance, we estimate masses of the 8 stars by utilising different combinations of seismic and non-seismic inputs. When introducing a correction to the Delta nu scaling relation as suggested by stellar models, for RGB stars we find excellent agreement with the expected masses from isochrone fitting, and with a distance modulus derived using independent methods. The offset with respect to independent masses is lower, or comparable with, the uncertainties on the average RGB mass (4-10%, depending on the combination of constraints used). Our results lend confidence to asteroseismic masses in the metal poor regime. We note that a larger sample will be needed to allow more stringent tests to be made of systematic uncertainties in all the observables (both seismic and non-seismic), and to explore the properties of RHB stars, and of different populations in the cluster.
BACKGROUND
African Americans have higher rates of nocturnal hypertension and less nocturnal blood pressure (BP) dipping compared with whites. Although nocturnal hypertension is associated with ...increased cardiovascular morbidity and mortality, its clinical significance among those with normal daytime BP is unclear. This paper reports the prevalence and correlates of isolated nocturnal hypertension (INH) in a population-based cohort of African Americans enrolled in the Jackson Heart Study (JHS).
METHODS
The study sample included 425 untreated, normotensive and hypertensive JHS participants who underwent 24-hour ambulatory BP monitoring (ABPM), echocardiography, and 24-hour urine collection. Multiple logistic regression and 1-way analysis of variance models were used to test the hypothesis that those with INH have worse target organ damage reflected by greater left ventricular (LV) mass and proteinuria compared with normotensive participants.
RESULTS
Based on 24-hour ABP profiles, 19.1% of participants had INH. In age and sex-adjusted models, participants with INH had greater LV mass compared with those who were normotensive (P = 0.02), as well as about 3 times the odds of LV hypertrophy and proteinuria (Ps < 0.10). However, multivariable adjustment reduced the magnitude and statistical significance of each of these differences.
CONCLUSIONS
INH was associated with increased LV mass compared with normo tension in a population-based cohort of African Americans enrolled in the JHS. There were trends toward a greater likelihood of LV hyper trophy and proteinuria among participants with INH vs. those who were normotensive. The clinical significance of the noted target organ damage should be explored in this population.
The angle \(\psi\) between a planet's orbital axis and the spin axis of its parent star is an important diagnostic of planet formation, migration, and tidal evolution. We seek empirical constraints ...on \(\psi\) by measuring the stellar inclination \(i_{\rm s}\) via asteroseismology for an ensemble of 25 solar-type hosts observed with NASA's Kepler satellite. Our results for \(i_{\rm s}\) are consistent with alignment at the 2-\(\sigma\) level for all stars in the sample, meaning that the system surrounding the red-giant star Kepler-56 remains as the only unambiguous misaligned multiple-planet system detected to date. The availability of a measurement of the projected spin-orbit angle \(\lambda\) for two of the systems allows us to estimate \(\psi\). We find that the orbit of the hot-Jupiter HAT-P-7b is likely to be retrograde (\(\psi=116.4^{+30.2}_{-14.7}\:{\rm deg}\)), whereas that of Kepler-25c seems to be well aligned with the stellar spin axis (\(\psi=12.6^{+6.7}_{-11.0}\:{\rm deg}\)). While the latter result is in apparent contradiction with a statement made previously in the literature that the multi-transiting system Kepler-25 is misaligned, we show that the results are consistent, given the large associated uncertainties. Finally, we perform a hierarchical Bayesian analysis based on the asteroseismic sample in order to recover the underlying distribution of \(\psi\). The ensemble analysis suggests that the directions of the stellar spin and planetary orbital axes are correlated, as conveyed by a tendency of the host stars to display large inclination values.
We investigate the spherical harmonic degree (l) dependence of the "seismic" quasi-biennial oscillation (QBO) observed in low-degree solar p-mode frequencies, using Sun-as-a-star Birmingham Solar ...Oscillations Network (BiSON) data. The amplitude of the seismic QBO is modulated by the 11-yr solar cycle, with the amplitude of the signal being largest at solar maximum. The amplitude of the signal is noticeably larger for the l=2 and 3 modes than for the l=0 and 1 modes. The seismic QBO shows some frequency dependence but this dependence is not as strong as observed in the 11-yr solar cycle. These results are consistent with the seismic QBO having its origins in shallow layers of the interior (one possibility being the bottom of the shear layer extending 5per cent below the solar surface). Under this scenario the magnetic flux responsible for the seismic QBO is brought to the surface (where its influence on the p modes is stronger) by buoyant flux from the 11-yr cycle, the strong component of which is observed at predominantly low-latitudes. As the l=2 and 3 modes are much more sensitive to equatorial latitudes than the l=0 and 1 modes the influence of the 11-yr cycle on the seismic QBO is more visible in l=2 and 3 mode frequencies. Our results imply that close to solar maximum the main influence of the seismic QBO occurs at low latitudes (<45 degrees), which is where the strong component of the 11-yr solar cycle resides. To isolate the latitudinal dependence of the seismic QBO from the 11-yr solar cycle we must consider epochs when the 11-yr solar cycle is weak. However, away from solar maximum, the amplitude of the seismic QBO is weak making the latitudinal dependence hard to constrain.
The purpose of this publication was to inform surgeons as to the modern state‐of‐the‐art evidence‐based guidelines for management of the recurrent laryngeal nerve invaded by malignancy through ...blending the domains of 1) surgical intraoperative information, 2) preoperative glottic function, and 3) intraoperative real‐time electrophysiologic information. These guidelines generated by the International Neural Monitoring Study Group (INMSG) are envisioned to assist the clinical decision‐making process involved in recurrent laryngeal nerve management during thyroid surgery by incorporating the important information domains of not only gross surgical findings but also intraoperative recurrent laryngeal nerve functional status and preoperative laryngoscopy findings. These guidelines are presented mainly through algorithmic workflow diagrams for convenience and the ease of application. These guidelines are published in conjunction with the INMSG Guidelines Part I: Staging Bilateral Thyroid Surgery With Monitoring Loss of Signal.
Level of Evidence: 5
Laryngoscope, 128:S18–S27, 2018
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