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Post-stroke fatigue (PSF) is a common symptom associated with disability and decreased quality of life. Distinction can be made between perceived fatigue and fatigability. The first aim of this study was to evaluate the prevalence of perceived fatigue and fatigability amongst patients with chronic stroke and to explore how these two parameters relate. The second aim was to study the relationship between modifiable factors (sleep disorders, anxiety, depression and activities of daily living) and fatigue in this population. Sixty-two patients with chronic stroke (> 6 months) were included. Perceived fatigue was evaluated using the Fatigue Severity Scale (FSS). Motor fatigability was assessed with the percent change in meters walked from first to last minute of the 6-min Walk Test and an isometric muscular fatigability test. Subjects also completed self-report questionnaires assessing anxiety and depression (Hospital Anxiety and Depression Scale—HADS), sleep quality (Pittsburgh Sleep Quality Index—PSQI) and activity limitations (ACTIVLIM-stroke). Seventy-one percent of participants presented PSF. There was no correlation between the FSS and motor fatigability. FSS significantly correlated with HADS-Anxiety (ρ= 0.53, P< 0.001), HADS-depression (ρ= 0.63, P< 0.001), PSQI (ρ= 0.51, P< 0.001) and ACTIVLIM (ρ= − 0.30, P< 0.05). A linear regression model showed that the HADS-Depression, the PSQI and the ACTIVLIM explained 46% of the variance of the FSS. A high proportion of chronic stroke patients presents PSF, with no relation between their fatigue and fatigability. Perceived fatigue is associated with potentially modifiable factors: anxious and depressive symptoms, poor sleep quality and activity limitations. Registered at ClinicalTrials.gov (NCT04277234) (21/02/2019).

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The main purpose of this paper is to investigate the possible existence of a metallicity dependence of the overshooting from main sequence star turbulent cores. We focus on objects with masses in the range ~$ 2.5~{M}_{\odot}$–~$25~{M}_{\odot}$. Evolutionary time scale ratios are compared with star number ratios on the main sequence. Star populations are synthesized using grids of evolutionary tracks computed with various overshooting amounts. Observational material is provided by the large and homogeneous photometric database of the OGLE 2 project for the Magellanic clouds. Attention is paid to the study of uncertainties: distance modulus, intergalactic and interstellar reddening, IMF slope and average binarity rate. Rotation and the chemical composition gradient are also considered. The result for the overshooting distance is $l_{\mathrm{over}}^{\mathrm{\tiny SMC}}= 0.40^{+0.12}_{-0.06}~\mathrm{H}_{\mathrm{p}}$($Z_{0}=0.004$) and $l_{\mathrm{over}}^{\mathrm{\tiny LMC}}= 0.10^{+0.17}_{-0.10}~\mathrm{H}_{\mathrm{p}}$($Z_{0}=0.008$) suggesting a possible dependence of the extent of the mixed central regions with metallicity within the considered mass range. Unfortunately it is not yet possible to fully disentangle the effects of mass and chemical composition.

We extend the colour calibration of the widely used BaSeL standard stellar library (Lejeune et al. 1997, 1998) to non-solar metallicities, down to ${\rm [Fe/H]} \sim -2.0$dex. Surprisingly, we find that at the present epoch it is virtually impossible to establish a unique calibration ofUBVRIJHKL colours in terms of stellar metallicity ${\rm [Fe/H]}$which is consistent simultaneously with both colour-temperature relations and colour-absolute magnitude diagrams (CMDs) based on observed globular cluster photometry data and on published, currently popular standard stellar evolutionary tracks and isochrones.The problem appears to be related to the long-standing incompleteness in our understanding of convection in late-type stellar evolution, but is also due to a serious lack of relevant observational calibration data that would help resolve, or at least further significant progress towards resolving this issue. In view of the most important applications of the BaSeL library, we here propose two different metallicity calibration versions: (1) the “WLBC 99” library, which consistently matches empirical colour-temperature relations and which, therefore, should make an ideal tool for the study of individual stars; and (2), the “PADOVA 2000” library, which provides isochrones from the Padova 2000 grid (Girardi et al. [CITE]) that successfully reproduce Galactic globular-cluster colour-absolute magnitude diagrams and which thus should prove particularly useful for studies of collective phenomena in stellar populations in clusters and galaxies.

We compare the accurate empirical mass-luminosity (M-L) relation based on five Hyades binary systems to predictions of stellar models calculated with various input parameters (helium, metallicity and age) or physics (mixing-length ratio, model atmosphere, equation of state and microscopic diffusion). Models based on a helium content $Y\sim 0.28$inferred from the $\Delta Y/\Delta Z$enrichment law are more than 3σbeyond the observations, suggesting that the Hyades initial helium abundance is lower than expected from its supersolar metallicity. With the photometric metallicity ($\mathrm{[Fe/H]}$= $0.144\pm 0.013$dex, Grenon [CITE]) we derive $Y=0.255\pm0.009$. Because of the (Y, $\mathrm{[Fe/H]}$) degeneracy in the M-L plane, the uncertainty grows to $\Delta Y=0.013$if the metallicity from spectroscopy is adopted ($\mathrm{[Fe/H]}$= $0.14\pm0.05$dex, Cayrel de Strobel et al. [CITE]). We use these results to discuss the Hertzsprung-Russell (HR) diagram of the Hyades, in the (MV, $B-V$) plane, based on the very precise Hipparcos dynamical parallaxes. Present models fit the tight observed sequence very well except at low temperatures. We show that the HR diagram does not bring further constraints on the helium abundance or metallicity of the cluster. In the low mass region of the HR diagram sensitive to the mixing-length parameter (${\alpha_\mathrm{MLT}}$), the slope of the main sequence (MS) suggests that ${\alpha_\mathrm{MLT}}$could decrease from a solar (or even supersolar) value at higher mass to subsolar values at low mass, which is also supported by the modeling of the vB22 M-L relation. We find that the discrepancy at low temperatures (($B-V$) $\ga 1.2$) remains, even if an improved equation of state or better model atmospheres are used. Finally, we discuss the positions of the stars at turn-off in the light of their observed rotation rates and we deduce that the maximum age of the Hyades predicted by the present models is ~650 Myr.

We have used an updated version of the empirically and semi-empirically calibrated BaSeLlibrary of synthetic stellar spectra of Lejeune et al.([CITE], [CITE]) and Westera et al.([CITE]) to calculate synthetic photometry in the (UBV)J(RI)CJHKLL′ M, HST-WFPC2, Geneva, and Washington systems for the entire set of non-rotating Geneva stellar evolution models covering masses from 0.4-0.8 to 120-150 $M_{\odot}$and metallicities $Z=0.0004$(1/50 $Z_{\odot}$) to 0.1 (5 $Z_{\odot}$). The results are provided in a database which includes all individual stellar tracks and the corresponding isochrones covering ages from 103yr to 16-20 Gyr in time steps of $\Delta \log t=$0.05 dex. The database also includes a new grid of stellar tracks of very metal-poor stars ($Z=0.0004$) from $0.8{-}150$$M_{\odot}$calculated with the Geneva stellar evolution code.

A standard library of theoretical stellar spectra intended for multiple synthetic photometry applications including spectral evolutionary synthesis is presented. The grid includes M dwarf model spectra, hence complementing the first library version established in Paper I (Lejeune et al. 1997). It covers wide ranges of fundamental parameters: $T_{\mathrm{eff}}$: 50 000 K ~ 2000 K, $\log g$: 5.5 $\sim -1.02$, and $[M/H]$: $+1.0 \sim -5.0$. A correction procedure is also applied to the theoretical spectra in order to provide color-calibrated flux distributions over a large domain of effective temperatures. For this purpose, empirical $T_{\mathrm{eff}}$–color calibrations are constructed between 11500 K and 2000 K, and semi-empirical calibrations for non-solar abundances ($[M/H]$$= -3.5$to +1.0) are established. Model colors and bolometric corrections for both the original and the corrected spectra, synthesized in the $(UBV)_{\rm J}(RI)_{\rm C}JHKLL'M$system, are given for the full range of stellar parameters. We find that the corrected spectra provide a more realistic representation of empirical stellar colors, though the method employed is not completely adapted to the lowest temperature models. In particular the original differential colors of the grid implied by metallicity and/or luminosity changes are not preserved below 2500 K. Limitations of the correction method used are also discussed.

The Basel Stellar Library (BaSeL) is a library of synthetic spectra which has already been used in various astrophysical applications (stellar cluster studies, characterization and choice of the COROT potential targets, eclipsing binaries,⃛). This library could provide useful indications to 1) choose the best photometric system for the GAIA strategy by evaluating their expected performances and 2) apply systematically the BaSeL models for any sample of the GAIA targets. In this context, we describe one of the future developments of the BaSeL interactive web site to probe the GAIA photometric data: an automatic determination of atmospheric parameters from observed colours.

Physical activity (PA) level of end-stage renal disease (ESRD) patients after renal transplantation (TP) is a largely unexplored field, although it is an important component of quality of life.