Context. High-resolution spectroscopy across spatially resolved stellar surfaces aims at obtaining spectral-line profiles that are free from rotational broadening; the gradual changes of these profiles from disk center toward the stellar limb reveal properties of atmospheric fine structure, which are possible to model with 3D hydrodynamics. Aims. Previous such studies have only been carried out for the Sun but are now extended to other stars. In this work, profiles of photospheric spectral lines are retrieved across the disk of the planet-hosting star HD 209458 (G0 V). Methods. During exoplanet transit, stellar surface portions successively become hidden and differential spectroscopy provides spectra of small surface segments temporarily hidden behind the planet. The method was elaborated in Paper I, with observable signatures quantitatively predicted from hydrodynamic simulations. Results. From observations of HD 209458 with spectral resolution λ/∆λ ∼ 80 000, photospheric Fe I line profiles are obtained at several center-to-limb positions, reaching adequately high S/N after averaging over numerous similar lines. Conclusions. Retrieved line profiles are compared to synthetic line profiles. Hydrodynamic 3D models predict, and current observations confirm, that photospheric absorption lines become broader and shallower toward the stellar limb, reflecting that horizontal velocities in stellar granulation are greater than vertical velocities. Additional types of 3D signatures will become observable with the highest resolution spectrometers at large telescopes.Key words. stars: atmospheres -techniques: spectroscopic -line: profiles -hydrodynamics -planets and satellites: gaseous planetsstars: solar-type Spatially resolved stellar spectraThree-dimensional and time-dependent hydrodynamic simulations provide realistic descriptions of the atmospheres of various classes of stars, and spectra computed from such models can be used to determine precise properties of the star and its exoplanets. To constrain and evolve such models, observations beyond the ordinary spectrum of integrated starlight are desirable. Spectral-line syntheses in 3D atmospheres show a rich variety of phenomena characterizing stellar hydrodynamics, which are seen especially in the gradual changes of photospheric line profile strengths, shapes, asymmetries, and wavelength shifts from the center of the disk toward the stellar limb. However, direct comparisons between theory and spectral-line observations have in the past only been possible for the spatially resolved Sun (e.g., Lind et al. 2017). In Paper I (Dravins et al. 2017), we examined theoretically predicted spatially resolved signatures for a group of main-sequence stellar models with temperatures between 6730 and 3960 K. Corresponding observations are feasible during exoplanet transits when small stellar surface portions successively become hidden, and differential spectroscopy between different transit phases can provide spectra of small surface segments temporarily hidden behind the pla...

Context. High-precision stellar analyses require hydrodynamic modeling to interpret chemical abundances or oscillation modes. Exoplanet atmosphere studies require stellar background spectra to be known along the transit path while detection of Earth analogs require stellar microvariability to be understood. Hydrodynamic 3D models can be computed for widely different stars but have been tested in detail only for the Sun with its resolved surface features. Model predictions include spectral line shapes, asymmetries, and wavelength shifts, and their center-to-limb changes across stellar disks. Aims. We observe high-resolution spectral line profiles across spatially highly resolved stellar surfaces, which are free from the effects of spatial smearing and rotational broadening present in full-disk spectra, enabling comparisons to synthetic profiles from 3D models. Methods. During exoplanet transits, successive stellar surface portions become hidden and differential spectroscopy between various transit phases provides spectra of small surface segments temporarily hidden behind the planet. Planets cover no more than ∼1% of any main-sequence star, enabling high spatial resolution but demanding very precise observations. Realistically measurable quantities are identified through simulated observations of synthetic spectral lines. Results. In normal stars, line profile ratios between various transit phases may vary by ∼0.5%, requiring S /N 5000 for meaningful spectral reconstruction.While not yet realistic for individual spectral lines, this is achievable for cool stars by averaging over numerous lines with similar parameters. Conclusions. For bright host stars of large transiting planets, spatially resolved spectroscopy is currently practical. More observable targets are likely to be found in the near future by ongoing photometric searches.

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Among patients who used EMS on multiple occasions, the most common symptoms on-scene were dyspnea, chest pain, and abdominal pain. The most common final diagnosis was chronic obstructive pulmonary disease. In 13.0%, the final diagnosis of a potentially life-threatening condition was indicated. In a minority of these cases, the assessment on-scene was judged as potentially inappropriate. Tärnqvist J , Dahlén E , Norberg G , Magnusson C , Herlitz J , Strömsöe A , Axelsson C , Andersson Hagiwara M . On-scene and final assessments and their interrelationship among patients who use the EMS on multiple occasions. Prehosp Disaster Med. 2017;32(5):528-535.

The aim of this study was to compare estimated glomerular filtration rate (eGFR) with creatinine (eGFRcrea) and cystatin C (eGFRcys) in geriatric and frail patients. A retrospective, cross-sectional study was performed at a geriatric clinic in Stockholm (n = 95). The revised Lund–Malmö equation was used to calculate eGFRcrea and the Caucasian-Asian-Pediatric-Adult (CAPA) equation was used for eGFRcys. The absolute mean percentage difference between eGFRcrea and eGFRcys was used as a surrogate measure for accuracy in eGFR. Other outcome measures were consistency expressed in Lin’s concordance correlation coefficient and the proportion of consistent staging of renal failure. Subgroup analyses were performed with regard to frailty (according to Clinical Frailty Scale) and age. eGFRcys estimated lower GFR than eGFRcrea across the entire study population as well as in all subgroups (p < 0.05). Difference between the estimates increased with increasing frailty (r2 = 0.15, p < 0.01), but was not significantly affected by age (r2 = 0.004, p = 0.55). In conclusion, eGFRcys was significantly lower compared to eGFRcrea in geriatric and frail patients. Moreover, frailty had greater impact than age on the accuracy of eGFR. However, this study cannot determine if any of the estimates are preferable over the other in this patient group.