A Bayesian method for detecting stellar flares

We present a Bayesian-odds-ratio-based algorithm for detecting stellar flares in light curve data. We assume flares are described by a model in which there is a rapid rise with a half-Gaussian profile, followed by an exponential decay. Our signal model also contains a polynomial background model. This is required to fit underlying light curve variations that are expected in the data, which could otherwise partially mimic a flare. We characterise the false alarm probability and efficiency of this method and compare it with a simpler thresholding method based on that used in Walkowicz et al (2011). We find our method has a significant increase in detection efficiency for low signal-to-noise ratio (S/N) flares. For a conservative false alarm probability our method can detect 95% of flares with S/N less than ~20, as compared to S/N of ~25 for the simpler method. As an example we have applied our method to a selection of stars in Kepler Quarter 1 data. The method finds 687 flaring stars with a total of 1873 flares after vetos have been applied. For these flares we have characterised their durations and and signal-to-noise ratios.Comment: Accepted for MNRAS. The code used for the analysis can be found at https://github.com/BayesFlare/bayesflare/releases/tag/v1.0.

Planet formation around stars of various masses: The snow line and the frequency of giant planets

We use a semi-analytic circumstellar disk model that considers movement of the snow line through evolution of accretion and the central star to investigate how gas giant frequency changes with stellar mass. The snow line distance changes weakly with stellar mass; thus giant planets form over a wide range of spectral types. The probability that a given star has at least one gas giant increases linearly with stellar mass from 0.4 M_sun to 3 M_sun. Stars more massive than 3 M_sun evolve quickly to the main-sequence, which pushes the snow line to 10-15 AU before protoplanets form and limits the range of disk masses that form giant planet cores. If the frequency of gas giants around solar-mass stars is 6%, we predict occurrence rates of 1% for 0.4 M_sun stars and 10% for 1.5 M_sun stars. This result is largely insensitive to our assumed model parameters. Finally, the movement of the snow line as stars >2.5 M_sun move to the main-sequence may allow the ocean planets suggested by Leger et. al. to form without migration.Comment: Accepted to ApJ. 12 pages of emulateap

Evidence of Nodal Line in the Superconducting Gap Symmetry of Noncentrosymmetric ThCoC2_{2}

The newly discovered noncentrosymmetric superconductor ThCoC$_{2}$ exhibits numerous unconventional behavior in the field dependent heat capacity data. Here we present the first measurement of the gap symmetry of ThCoC$_{2}$ by muon spin rotation/relaxation $(\mu$SR) measurements. Temperature dependence of the magnetic penetration depth measured using the transverse field $\mu$SR measurement reveal the evidence of nodal pairing symmetry. To understand these findings, we carry out the calculations of superconducting pairing eigenvalue and eigenfunction symmetry due to the spin-fluctuation mechanism, by directly implemented the {\it ab-initio} band structures. We find that the system possesses a single Fermi surface with considerable three-dimensionality, and hence a strong nesting along the $k_z$-direction. Such a nesting promotes a superconducting pairing with a $\cos{k_z}$-like symmetry with a prominent nodal line on the $k_z=\pm\pi/2$ plane. The result agrees well with the experimental data.Comment: 3 pages, 5 figure

A qualitative exploration of key stakeholders’ views and perceptions in relation to organisational change for the implementation of polypharmacy management in Oman.

Polypharmacy contributes to patient non-adherence and increases medication harm. Barriers to implementation prevent desired outcomes when addressing inappropriate polypharmacy at organisational levels and there is a need for theory-based strategies for change management. The objective of this study was to explore the views and perceptions of key stakeholders in relation to organisational change for the development and implementation of a polypharmacy management healthcare strategy in Oman. Qualitative face to face interviews started in March 2022 with key stakeholders in Oman Ministry of Health (MOH) including leaders from practice of Medical, pharmacy and nursing as well as academic leaders from school of medicine, pharmacy and nursing. The interview schedule developed based on a scoping review, Kotter's first three steps of leading change and grounded in the consolidated Framework for Implementation Research (CIFR). Interviews were digitally recorded, transcribed, and analysed independently by at least two researchers using CFIR as a coding framework. Ethics approval was in place prior to data generation. Identified themes related to views and perceptions of key stakeholders in relation to the topic area. To date, ten interviews have been conducted with directors of medical (n=2), pharmacy (2) and nursing practice (1), academic healthcare leaders (3), a healthcare policy developer (1) and patient safety leader (1). Additional interviews are planned and will continue until data saturation. Emerging themes show that participants have views that polypharmacy is a burden on healthcare services and there is a need for organisational change in relation to polypharmacy management. Perceptions of reported organisational level barriers were; fragmentation of care, lack of systems for coordination among healthcare providers, absence of electronic link between the government and private sector, lack of sense of urgency among leaders regarding the polypharmacy and shortage of pharmacists. Facilitators were; the presence of well-developed electronic health system and leadership support. There is a need for for organisational change in relation to polypharmacy management in Oman. Further research is needed to obtain consensus of Omani stakeholders on the plan for a strategic framework for organisational change in relation to polypharmacy management

Implementation frameworks for polypharmacy management within healthcare organisations: a scoping review.

Several guidelines support polypharmacy management in individual patients. More organisational-level focus is needed on the use of implementation frameworks. The aim of this scoping review was to characterise the peer-reviewed literature on implementation frameworks, focussing on barriers and facilitators to implementation at organisational level in the context of polypharmacy management. A scoping review protocol was devised, supporting retrieval of studies published in English, reporting from any sector of practice. Medline, International Pharmaceutical Abstracts, Cumulative Index of Nursing and Allied Health Literature and Business Source Complete were searched to January 2022 using Medical Subject Headings including: 'polypharmacy', 'deprescriptions', 'strategic planning' and 'organizational innovation'. A narrative approach to data synthesis was applied. Searching, data extraction and synthesis were undertaken independently by two reviewers. After screening 797 records, eight papers remained. Two were descriptive, outlining details of specific initiatives; six used qualitative methods to explore determinants for implementation, including barriers and enablers. Barriers at the organisation level included: poor organisational culture with a lack of sense of urgency and national plans, resource availability and communication issues including patient information and at transitions of care. Organisational facilitators included availability of government funding and regulatory environment promoting patient safety, a national emphasis on quality of care for older adults, co-ordinated national efforts and local evidence. Limited literature focusses on the use of implementation frameworks at organisational levels. This review highlights the need for further work on implementation frameworks in this context to help achieve effective organisational change

Constraints on the Primordial Magnetic Field from σ8\sigma_8

A primordial magnetic field (PMF) can affect the evolution of density field fluctuations in the early universe.In this paper we constrain the PMF amplitude $B_\lambda$ and power spectral index $n_\mathrm{B}$ by comparing calculated density field fluctuations with observational data, i.e. the number density fluctuation of galaxies.We show that the observational constraints on cosmological density fluctuations, as parameterized by $\sigma_8$, lead to strong constraints on the amplitude and spectral index of the PMF.Comment: 11 pages, 1 figure, accepted for publication as Phys. Rev.