Aims. We investigated the theoretical biases affecting the asteroseismic grid-based estimates of stellar mass, radius, and age in the presence of a mismatch between the heavy element mixture of ...observed stars and stellar models. Methods. We performed a controlled simulation adopting a stellar effective temperature, Fe/H, an average large frequency spacing, and a frequency of maximum oscillation power as observational constraints. Synthetic stars were sampled from grids of stellar models computed with different α /Fe values from 0.0 to 0.4. The mass, radius, and age of these objects were then estimated by adopting a grid of models with a fixed α /Fe value of 0.0. The experiment was repeated assuming different sets of observational uncertainties. In the reference scenario, we adopted an uncertainty of 1.5% in seismic parameters, 50 K in effective temperature, and 0.05 dex in Fe/H. A higher uncertainty in the atmospheric constraints was also adopted in order to explore the impact on the precision of the observations of the estimated stellar parameters. Results. Our Monte Carlo experiment showed that estimated parameters are biased up to 3% in mass, 1.5% in radius, and 4% in age when the reference uncertainty scenario was adopted. These values correspond to 45%, 48%, and 16% of the estimated uncertainty in the stellar parameters. These non-negligible biases in mass and radius disappear when adopting larger observational uncertainties because of the possibility of the fitting algorithm exploring a wider range of possible solutions. However, in this scenario, the age is significantly biased by −8%. Finally, we verified that the stellar mass, radius, and age can be estimated with a high accuracy by adopting a grid with the incorrect value of α /Fe if the metallicity Fe/H of the target is adjusted to match the Z in the fitting grid. In this scenario, the maximum bias in the age was reduced to 1.5%.
Context.
It is now well-known that pre-main-sequence models with inflated radii should be taken into account to simultaneously reproduce the colour-magnitude diagram and the lithium depletion pattern ...observed in young open star clusters.
Aims.
We tested a new set of pre-main-sequence models that include radius inflation due to the presence of starspots or to magnetic inhibition of convection. We used five clusters observed by the
Gaia
-ESO Survey that span the age range ∼10−100 Myr, in which these effects could be important.
Methods.
The
Gaia
-ESO Survey radial velocities were combined with astrometry from
Gaia
EDR3 to obtain clean lists of high-probability members for the five clusters. A Bayesian maximum likelihood method was adopted to fit the observed cluster sequences to theoretical predictions to derive the best model parameters and the cluster reddening and age. Models were calculated with different values of the mixing length parameter (
α
ML
= 2.0, 1.5 and 1.0) for the cases without spots or with effective spot coverage
β
spot
= 0.2 and 0.4. The models were also compared with the observed lithium depletion patterns.
Results.
To reproduce the colour-magnitude diagram and the observed lithium depletion pattern in Gamma Vel A and B and in 25 Ori, both a reduced convection efficiency, with
α
ML
= 1.0, and an effective surface spot coverage of about 20% are required. We obtained ages of 18
−4.0
+1.5
Myr and 21
−3.0
+3.5
Myr for Gamma Vel A and B, respectively, and 19
−7.0
+1.5
Myr for 25 Ori. However, a single isochrone is not sufficient to account for the lithium dispersion, and an increasing level of spot coverage as mass decreases seems to be required. On the other hand, the older clusters (NGC 2451 B at 30
−5.0
+3.0
Myr, NGC 2547 at 35
−4.0
+4.0
Myr, and NGC 2516 at 138
−42
+48
Myr) are consistent with standard models (i.e.
α
ML
= 2.0 and no spots) except at low masses: a 20% spot coverage appears to reproduce the sequence of M-type stars better and might explain the observed spread in lithium abundances.
Conclusions.
The quality of
Gaia
-ESO data combined with
Gaia
allows us to gain important insights on pre-main-sequence evolution. Models including starspots can provide a consistent explanation of the cluster sequences and lithium abundances observed in young clusters, although a range of starspot coverage is required to fully reproduce the data.
ObjectivesIn this study, we explored healthcare workers’ (HCWs) worry perception and its association with their work situation during the first wave of the COVID-19 pandemic.DesignA web-based ...multimethods survey including multiple choice and open-ended questions was used.SettingThe study was conducted at a university hospital in Sweden.ParticipantsAll HCWs who were working during the first wave of the COVID-19 pandemic in March–June 2020 were eligible. HCWs (n=6484, response rate=41%) from 69 departments fulfilled the study inclusion criteria and responded to the survey. Of them, we analysed data from the 3532 participants who replied to the open-ended questions (54% of the respondents).Main outcomes measuresWorry perception and its association with work conditions among HCWs.Results29% (n=1822) and 35% (n=2235) of the responding HCWs experienced a daily or more than daily strong worry of being infected or infecting others with SARS-CoV-2. This finding could be further confirmed and explored with themes from the qualitative results: ‘ambiguity of feeling safe and secure’, ‘being obliged to adapt to a new reality’ and ‘into the unknown’. The themes consisted of 6 main categories and 15 subcategories. The findings revealed that the two main drivers of worry perceived by HCWs were lack of personal protective equipment and fear of bringing the virus home to their families and friends.ConclusionsWorries of getting infected are common among HCWs during crises such as the COVID-19 pandemic. Several factors are raised that plausibly could minimise the negative effects of worry among HCWs. Thus, effective preventive work plans should be created, promoted and communicated in order to minimise the effects of such crises and support HCWs. By focusing on effective communication and preparedness, including access to relevant protective equipment and providing general support to HCWs, the work environment and patient care could be sustained during a crisis such as the COVID-19 pandemic.
This study compared the characteristics of a population of Swedish patients in forensic psychiatric care in the year 2010 and 2018, with the goal of identifying similarities and differences in ...sociodemographic and clinical outcomes during the study period.
Significant changes in patient characteristics and treatment aspects were found, although similarities between the years were more common. Schizophrenia, schizotypal and delusional disorders were the most predominant primary diagnoses characterizing forensic psychiatric patients. From 2010 to 2018 there was also a development in care conditions supporting a shift from inpatient to outpatient care and from first-generation antipsychotic/neuroleptic to second-generation antipsychotics/atypical antipsychotics. More liberty restrictive such as physical restraints and forcible medication diminished while less restrictive coercive measures increased. There was also a decrease in the length of stay in forensic psychiatric care among those treated 2018 compared to those treated 2010, something that emerged as particularly discernible among male patients.
In conclusion, the results from this study illustrate the similarities among a Swedish forensic psychiatric population between the years of 2010 and 2018, while also reflecting some changes in patient characteristics and clinical practice during the study period.
Posidonia oceanica (L.) Delile is an endemic Mediterranean marine plant of extreme ecological importance. Previous in vitro and in vivo studies have demonstrated the potential antidiabetic properties ...of P. oceanica leaf extract. Intestinal glucose transporters play a key role in glucose homeostasis and represent novel targets for the management of diabetes. In this study, the ability of a hydroalcoholic P. oceanica leaf extract (POE) to modulate intestinal glucose transporters was investigated using Caco-2 cells as a model of an intestinal barrier. The incubation of cells with POE significantly decreased glucose uptake by decreasing the GLUT2 glucose transporter levels. Moreover, POE had a positive effect on the barrier integrity by increasing the Zonulin-1 levels. A protective effect exerted by POE against oxidative stress induced by chronic exposure to high glucose concentrations or tert-butyl hydroperoxide was also demonstrated. This study highlights for the first time the effect of POE on glucose transport, intestinal barrier integrity, and its protective antioxidant effect in Caco-2 cells. These findings suggest that the P. oceanica phytocomplex may have a positive impact by preventing the intestinal cell dysfunction involved in the development of inflammation-related disease associated with oxidative stress.
The field of terahertz (THz) waveguides continues to grow rapidly, with many being tailored to suit the specific demands of a particular final application. Here, we explore waveguides capable of ...enabling efficient and accurate power delivery within cryogenic environments (< 4 K). The performance of extruded hollow cylindrical metal waveguides made of un-annealed and annealed copper, as well as stainless steel, have been investigated for bore diameters between 1.75 - 4.6 mm, and at frequencies of 2.0, 2.85 and 3.4 THz, provided by a suitable selection of THz quantum cascade lasers. The annealed copper resulted in the lowest transmission losses, < 3 dB/m for a 4.6 mm diameter waveguide, along with 90° bending losses as low as ~2 dB for a bend radius of 15.9 mm. The observed trends in losses were subsequently analyzed and related to measured inner surface roughness parameters. These results provide a foundation for the development of a wide array of demanding low-temperature THz applications, and enabling the study of fundamental physics.
Spotting trends: Upon going from TbIII to YbIII centers in the complexes of the DOTA4− ligand, a reorientation of the easy axis of magnetization from perpendicular to parallel to the LnO bond of the ...apical water molecule is experimentally observed and theoretically predicted (see picture; SMM=single‐molecule magnet). Only ions with an odd number of electrons show slow relaxation of the magnetization.
Abstract Bipolar disorder (BD) adversely affects daily activities/functioning. The Sheehan Disability Scale (SDS) assesses disability in work/school activities, family relationships, and social ...functioning, and it evaluates the functional impact of psychiatric disorders. BD outpatients from 21 U.S. sites completed a battery of validated instruments (including the SDS) three times over 8–12 weeks. Instrument reliability (internal consistency, test–retest), validity (construct, convergent validity, known groups) and responsiveness were measured. There were missing data for the SDS in 2% of the 225 subjects with BD. One factor explained 82% of the variance. All SDS items had rotated factor loadings on the first factor > 0.90, confirming the appropriateness of the SDS total score. Item-scale correlations surpassed 0.40. There was excellent internal consistency reliability for the SDS total score (Cronbach's alpha = 0.89). Test–retest reliability was acceptable for the SDS total score (intraclass correlation coefficient = 0.73). Correlations with other instruments demonstrate convergent and divergent validity. The SDS total and item scores significantly discriminated between (self-rated) overall health status, clinician-rated functional status, and clinician-rated depression, evidencing known group validity. The SDS demonstrated ability to detect change over time. The SDS is a valid, reliable measure of disability and is responsive to change over time when used in subjects with BD.
The aim of this study is to provide insight into the psychosocial work situation of hospital managers during the first wave of the COVID-19 pandemic.
Mixed-effect modelling was used on survey data on ...job demands, job resources, job motivation, and work-life balance among over 500 managers working in 55 departments of a large Swedish university hospital in 2019 and 2020. Responses from 6011 employees were then used to stratify the analysis for COVID-19 exposure. Inductive content analysis was applied to open-ended questions on the managers' views on organisational prerequisites during the onset of the pandemic.
The proportion of managers reporting difficulties with role clarity, quantitative demands, decision-making authority, and emotional support, time for recovery at work, motivation deficits, or problems with work-life balance clearly increased during the first wave of the pandemic. The proportion of managers reporting negative responses was higher in departments with high COVID-19 exposure. The qualitative analysis shows that overall governance in terms of clear, fair, and well-communicated routines, resource allocation, and division of responsibilities constituted an important framework for managerial during the crisis. First-line managers also require a mandate to re-organize their roles and their teams to successfully adapt to the situation. Organisational and social support was also important resources.
This is the first study investigating healthcare managers' work situation during the first wave of the COVID-19 pandemic in a Swedish context. As expected, it indicates an increasingly strained work situation during the crisis, but it also provides findings on organisational prerequisites that allow healthcare managers to cope with stressful situations. In line with previous research on organisational resilience, the study provides suggestions for how higher-level managers can act in order to provide front-line managers with the organisational prerequisites they need to adapt, learn and develop successfully during times of unpredictability, insecurity, and rapid change in order to offer the best possible support to health care workers.
With a growing interest on inorganic ceramics based solid-state electrolytes for all-solid-state batteries, there is a need to maximise their density to optimise electrochemical performance and fuel ...impermeability. In this paper, we demonstrate the sensitivity of terahertz time-domain spectroscopy (THz-TDS) combined with effective medium theory to quantify the porosity or density of sodium superionic conductor (NaSICON)-based solid-state electrolyte (SSEs) pellets prepared at densities in the range of 2.2–2.9 g cm−3, corresponding to 50–90 % relative densities sintered at 900–1150 °C. The results of which, have been validated against complementary Archimedes analysis and mercury porosimetry highlighting the potential of THz-TDS for rapid, contactless, non-destructive electrolyte characterisation.
•Demonstrated sensitivity of terahertz radiation to NaSICON-based electrolyte.•NaSICON densities quantified using effective medium theory.•Estimated densities correlates to Archimedes analysis.•Estimated densities agrees with to mercury porosimetry data.
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