Stellar activity cycles and contribution of the deep layers knowledge

It is believed that magnetic activity on the Sun and solar-type stars are tightly related to the dynamo process driven by the interaction between rotation, convection, and magnetic field. However, the detailed mechanisms of this process are still incompletely understood. Many questions remain unanswered, e.g.: why some stars are more active than others?; why some stars have a flat activity?; why is there a Maunder minimum?; are all the cycles regular? A large number of prox- ies are typically used to study the magnetic activity of stars as we cannot resolve stellar discs. Recently, it was shown that asteroseismology can also be used to study stellar activity, making it an even more powerful tool. If short cycles are not so un- common, we expect to detect many of them with missions such as CoRoT, Kepler, and possibly the PLATO mission. We will review some of the latest results obtained with spectroscopic measurements. We will show how asteroseismology can help us to better understand the complex process of dynamo and illustrate how the CoRoT and Kepler missions are revolutionizing our knowledge on stellar activity. A new window is being opened over our understanding of the magnetic variability of stars.Comment: 7 pages. To appear in Astrophysics and Space Science Proceedings series of the 20th Stellar pulsation conference held in Granada (Spain) from 6 to 10 September 2011

Pilot study of a community pharmacist led program to treat hepatitis C virus among people who inject drugs

Background: People who inject drugs (PWID) are a key population for treatment with direct-acting antiviral medications (DAAs) to eliminate hepatitis C virus (HCV). We developed a Pharmacist, Physician, and Patient Navigator Collaborative Care Model (PPP-CCM) for delivery of HCV treatment; this study describes clinical outcomes related to HCV treatment (initial evaluation, treatment initiation, completion, and cure), as well as patient satisfaction. Methods: We conducted a single-arm prospective pilot study of adult PWID living with HCV. Participants completed baseline and six-month follow-up surveys, and treatment and outcomes were abstracted from electronic health records. Primary outcome was linkage to pharmacist for HCV evaluation; secondary outcomes included DAA initiation, completion, and cure, as well as patient-reported satisfaction. Results: Of the 40 PWID enrolled, mean age was 43.6 years, 12 (30 %) were female, 20 (50 %) were non-white, and 15 (38 %) were unhoused. Thirty-eight (95 %) were successfully linked to the pharmacist for initial evaluation. Of those, 21/38 (55 %) initiated DAAs, and 16/21 (76 %) completed treatment. Among those completing treatment who had viral load data to document whether they achieved “sustained virologic response'', i.e. cure, 10/11 (91 %) were found to be cured. There was high satisfaction with 100 % responding “agree or strongly agree” that they had a positive experience with the pharmacist. Conclusion: Nearly all participants in this pilot were successfully linked to the pharmacist for evaluation, and more than half were started on DAAs; results provide preliminary evidence of feasibility of pharmacist-led models of HCV treatment for PWID. Clinicaltrials.gov registration number: NCT04698629

Observing Dynamos in Cool Stars

The main aim of this paper is to introduce the most important observables that help us to investigate stellar dynamos and compare those to the modeling results. We give an overview of the available observational methods and data processing techniques that are suitable for such purposes, with touching upon examples of inadequate interpretations as well. Stellar observations are compared to the solar data in such a way, which ensures that the measurements are comparable in dimension, wavelength, and timescale. A brief outlook is given to the future plans and possibilities. A thorough review of this topic was published nearly a decade ago (Berdyugina 2005), now we focus on the experience that have been gathered since that time.Comment: 47 pages, accepted for publication in Space Science Review