| 1. |
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| 2. |
- Babusiaux, C., et al.
(författare)
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Observational Hertzsprung-Russell diagrams
- 2018
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Ingår i: Astronomy and Astrophysics. - : EDP Sciences. - 0004-6361 .- 1432-0746. ; 616
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Tidskriftsartikel (refereegranskat)abstract
- Context. Gaia Data Release 2 provides high-precision astrometry and three-band photometry for about 1.3 billion sources over the full sky. The precision, accuracy, and homogeneity of both astrometry and photometry are unprecedented. Aims. We highlight the power of the Gaia DR2 in studying many fine structures of the Hertzsprung-Russell diagram (HRD). Gaia allows us to present many different HRDs, depending in particular on stellar population selections. We do not aim here for completeness in terms of types of stars or stellar evolutionary aspects. Instead, we have chosen several illustrative examples. Methods. We describe some of the selections that can be made in Gaia DR2 to highlight the main structures of the Gaia HRDs. We select both field and cluster (open and globular) stars, compare the observations with previous classifications and with stellar evolutionary tracks, and we present variations of the Gaia HRD with age, metallicity, and kinematics. Late stages of stellar evolution such as hot subdwarfs, post-AGB stars, planetary nebulae, and white dwarfs are also analysed, as well as low-mass brown dwarf objects. Results. The Gaia HRDs are unprecedented in both precision and coverage of the various Milky Way stellar populations and stellar evolutionary phases. Many fine structures of the HRDs are presented. The clear split of the white dwarf sequence into hydrogen and helium white dwarfs is presented for the first time in an HRD. The relation between kinematics and the HRD is nicely illustrated. Two different populations in a classical kinematic selection of the halo are unambiguously identified in the HRD. Membership and mean parameters for a selected list of open clusters are provided. They allow drawing very detailed cluster sequences, highlighting fine structures, and providing extremely precise empirical isochrones that will lead to more insight in stellar physics. Conclusions. Gaia DR2 demonstrates the potential of combining precise astrometry and photometry for large samples for studies in stellar evolution and stellar population and opens an entire new area for HRD-based studies.
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| 3. |
- Brown, A. G. A., et al.
(författare)
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Gaia Data Release 2 Summary of the contents and survey properties
- 2018
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Ingår i: Astronomy and Astrophysics. - : EDP Sciences. - 0004-6361 .- 1432-0746. ; 616
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Tidskriftsartikel (refereegranskat)abstract
- Context. We present the second Gaia data release, Gaia DR2, consisting of astrometry, photometry, radial velocities, and information on astrophysical parameters and variability, for sources brighter than magnitude 21. In addition epoch astrometry and photometry are provided for a modest sample of minor planets in the solar system. Aims. A summary of the contents of Gaia DR2 is presented, accompanied by a discussion on the differences with respect to Gaia DR1 and an overview of the main limitations which are still present in the survey. Recommendations are made on the responsible use of Gaia DR2 results. Methods. The raw data collected with the Gaia instruments during the first 22 months of the mission have been processed by the Gaia Data Processing and Analysis Consortium (DPAC) and turned into this second data release, which represents a major advance with respect to Gaia DR1 in terms of completeness, performance, and richness of the data products. Results. Gaia DR2 contains celestial positions and the apparent brightness in G for approximately 1.7 billion sources. For 1.3 billion of those sources, parallaxes and proper motions are in addition available. The sample of sources for which variability information is provided is expanded to 0 : 5 million stars. This data release contains four new elements: broad-band colour information in the form of the apparent brightness in the G(BP) (330-680 nm) and G(RP) (630-1050 nm) bands is available for 1.4 billion sources; median radial velocities for some 7 million sources are presented; for between 77 and 161 million sources estimates are provided of the stellar effective temperature, extinction, reddening, and radius and luminosity; and for a pre-selected list of 14 000 minor planets in the solar system epoch astrometry and photometry are presented. Finally, Gaia DR2 also represents a new materialisation of the celestial reference frame in the optical, the Gaia-CRF2, which is the first optical reference frame based solely on extragalactic sources. There are notable changes in the photometric system and the catalogue source list with respect to Gaia DR1, and we stress the need to consider the two data releases as independent. Conclusions. Gaia DR2 represents a major achievement for the Gaia mission, delivering on the long standing promise to provide parallaxes and proper motions for over 1 billion stars, and representing a first step in the availability of complementary radial velocity and source astrophysical information for a sample of stars in the Gaia survey which covers a very substantial fraction of the volume of our galaxy.
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| 4. |
- Eyer, L., et al.
(författare)
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Gaia Data Release 2 Variable stars in the colour-absolute magnitude diagram
- 2019
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Ingår i: Astronomy and Astrophysics. - : EDP Sciences. - 0004-6361 .- 1432-0746. ; 623
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Tidskriftsartikel (refereegranskat)abstract
- Context. The ESA Gaia mission provides a unique time-domain survey for more than 1.6 billion sources with G less than or similar to 21 mag. Aims. We showcase stellar variability in the Galactic colour-absolute magnitude diagram (CaMD). We focus on pulsating, eruptive, and cataclysmic variables, as well as on stars that exhibit variability that is due to rotation and eclipses. Methods. We describe the locations of variable star classes, variable object fractions, and typical variability amplitudes throughout the CaMD and show how variability-related changes in colour and brightness induce "motions". To do this, we use 22 months of calibrated photometric, spectro-photometric, and astrometric Gaia data of stars with a significant parallax. To ensure that a large variety of variable star classes populate the CaMD, we crossmatched Gaia sources with known variable stars. We also used the statistics and variability detection modules of the Gaia variability pipeline. Corrections for interstellar extinction are not implemented in this article. Results. Gaia enables the first investigation of Galactic variable star populations in the CaMD on a similar, if not larger, scale as was previously done in the Magellanic Clouds. Although the observed colours are not corrected for reddening, distinct regions are visible in which variable stars occur. We determine variable star fractions to within the current detection thresholds of Gaia. Finally, we report the most complete description of variability-induced motion within the CaMD to date. Conclusions. Gaia enables novel insights into variability phenomena for an unprecedented number of stars, which will benefit the understanding of stellar astrophysics. The CaMD of Galactic variable stars provides crucial information on physical origins of variability in a way that has previously only been accessible for Galactic star clusters or external galaxies. Future Gaia data releases will enable significant improvements over this preview by providing longer time series, more accurate astrometry, and additional data types (time series BP and RP spectra, RVS spectra, and radial velocities), all for much larger samples of stars.
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| 5. |
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| 6. |
- Helmi, A., et al.
(författare)
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Gaia Data Release 2 Kinematics of globular clusters and dwarf galaxies around the Milky Way
- 2018
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Ingår i: Astronomy and Astrophysics. - : EDP Sciences. - 0004-6361 .- 1432-0746. ; 616:A12
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Tidskriftsartikel (refereegranskat)abstract
- Aims The goal of this paper is to demonstrate the outstanding quality of the second data release of the Gaia mission and its power for constraining many different aspects of the dynamics of the satellites of the Milky Way. We focus here on determining the proper motions of 75 Galactic globular clusters, nine dwarf spheroidal galaxies, one ultra-faint system, and the Large and Small Magellanic Clouds.Methods Using data extracted from the Gaia archive, we derived the proper motions and parallaxes for these systems, as well as their uncertainties. We demonstrate that the errors, statistical and systematic, are relatively well understood. We integrated the orbits of these objects in three different Galactic potentials, and characterised their properties. We present the derived proper motions, space velocities, and characteristic orbital parameters in various tables to facilitate their use by the astronomical community.Results Our limited and straightforward analyses have allowed us for example to (i) determine absolute and very precise proper motions for globular clusters; (ii) detect clear rotation signatures in the proper motions of at least five globular clusters; (iii) show that the satellites of the Milky Way are all on high-inclination orbits, but that they do not share a single plane of motion; (i v) derive a lower limit for the mass of the Milky Way of 9.1(-2.6)(+6.2) x 10(11) M-circle dot based on the assumption that the Leo I dwarf spheroidal is bound; (v) derive a rotation curve for the Large Magellanic Cloud based solely on proper motions that is competitive with line-of-sight velocity curves, now using many orders of magnitude more sources; and (v i) unveil the dynamical effect of the bar on the motions of stars in the Large Magellanic Cloud.Conclusions All these results highlight the incredible power of the Gaia astrometric mission, and in particular of its second data release.
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| 7. |
- Katz, D., et al.
(författare)
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Gaia Data Release 2 Mapping the Milky Way disc kinematics
- 2018
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Ingår i: Astronomy and Astrophysics. - : EDP Sciences. - 0004-6361 .- 1432-0746. ; 616
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Tidskriftsartikel (refereegranskat)abstract
- Context. The second Gaia data release (Gaia DR2) contains high-precision positions, parallaxes, and proper motions for 1.3 billion sources as well as line-of-sight velocities for 7.2 million stars brighter than G(RVS) = 12 mag. Both samples provide a full sky coverage. Aims. To illustrate the potential of Gaia DR2, we provide a first look at the kinematics of the Milky Way disc, within a radius of several kiloparsecs around the Sun. Methods. We benefit for the first time from a sample of 6.4 million F-G-K stars with full 6D phase-space coordinates, precise parallaxes (sigma((omega) over bar)/(omega) over bar <= 20%), and precise Galactic cylindrical velocities (median uncertainties of 0.9-1.4 km s(-1) and 20% of the stars with uncertainties smaller than 1 km s(-1) on all three components). From this sample, we extracted a sub-sample of 3.2 million giant stars to map the velocity field of the Galactic disc from similar to 5 kpc to similar to 13 kpc from the Galactic centre and up to 2 kpc above and below the plane. We also study the distribution of 0.3 million solar neighbourhood stars (r < 200 pc), with median velocity uncertainties of 0.4 km s(-1), in velocity space and use the full sample to examine how the over-densities evolve in more distant regions. Results. Gaia DR2 allows us to draw 3D maps of the Galactocentric median velocities and velocity dispersions with unprecedented accuracy, precision, and spatial resolution. The maps show the complexity and richness of the velocity field of the galactic disc. We observe streaming motions in all the components of the velocities as well as patterns in the velocity dispersions. For example, we confirm the previously reported negative and positive galactocentric radial velocity gradients in the inner and outer disc, respectively. Here, we see them as part of a non-axisymmetric kinematic oscillation, and we map its azimuthal and vertical behaviour. We also witness a new global arrangement of stars in the velocity plane of the solar neighbourhood and in distant regions in which stars are organised in thin substructures with the shape of circular arches that are oriented approximately along the horizontal direction in the U - V plane. Moreover, in distant regions, we see variations in the velocity substructures more clearly than ever before, in particular, variations in the velocity of the Hercules stream. Conclusions. Gaia DR2 provides the largest existing full 6D phase-space coordinates catalogue. It also vastly increases the number of available distances and transverse velocities with respect to Gaia DR1. Gaia DR2 offers a great wealth of information on the Milky Way and reveals clear non-axisymmetric kinematic signatures within the Galactic disc, for instance. It is now up to the astronomical community to explore its full potential.
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| 8. |
- Mignard, F., et al.
(författare)
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Gaia Data Release 2 The celestial reference frame (Gaia-CRF2)
- 2018
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Ingår i: Astronomy and Astrophysics. - : EDP SCIENCES S A. - 0004-6361 .- 1432-0746. ; 616
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Tidskriftsartikel (refereegranskat)abstract
- Context: The second release of Gaia data (Gaia DR2) contains the astrometric parameters for more than half a million quasars. This set defines a kinematically non-rotating reference frame in the optical domain. A subset of these quasars have accurate VLBI positions that allow the axes of the reference frame to be aligned with the International Celestial Reference System (ICRF) radio frame.Aims: We describe the astrometric and photometric properties of the quasars that were selected to represent the celestial reference frame of Gaia DR2 (Gaia-CRF2), and to compare the optical and radio positions for sources with accurate VLBI positions.Methods: Descriptive statistics are used to characterise the overall properties of the quasar sample. Residual rotation and orientation errors and large-scale systematics are quantified by means of expansions in vector spherical harmonics. Positional differences are calculated relative to a prototype version of the forthcoming ICRF3.Results: Gaia-CRF2 consists of the positions of a sample of 556 869 sources in Gaia DR2, obtained from a positional cross-match with the ICRF3-prototype and AllWISE AGN catalogues. The sample constitutes a clean, dense, and homogeneous set of extragalactic point sources in the magnitude range G similar or equal to 16 to 21 mag with accurately known optical positions. The median positional uncertainty is 0.12 mas for G < 18 mag and 0.5 mas at G = 20 mag. Large-scale systematics are estimated to be in the range 20 to 30 mu as. The accuracy claims are supported by the parallaxes and proper motions of the quasars in Gaia DR2. The optical positions for a subset of 2820 sources in common with the ICRF3-prototype show very good overall agreement with the radio positions, but several tens of sources have significantly discrepant positions.Conclusions: Based on less than 40% of the data expected from the nominal Gaia mission, Gaia-CRF2 is the first realisation of a non-rotating global optical reference frame that meets the ICRS prescriptions, meaning that it is built only on extragalactic sources. Its accuracy matches the current radio frame of the ICRF, but the density of sources in all parts of the sky is much higher, except along the Galactic equator.
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| 9. |
- Spoto, F., et al.
(författare)
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Gaia Data Release 2 : Observations of solar system objects
- 2018
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Ingår i: Astronomy and Astrophysics. - : EDP SCIENCES S A. - 0004-6361 .- 1432-0746. ; 616
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Tidskriftsartikel (refereegranskat)abstract
- Context: The Gaia spacecraft of the European Space Agency (ESA) has been securing observations of solar system objects (SSOs) since the beginning of its operations. Data Release 2 (DR2) contains the observations of a selected sample of 14,099 SSOs. These asteroids have been already identified and have been numbered by the Minor Planet Center repository. Positions are provided for each Gaia observation at CCD level. As additional information, complementary to astrometry, the apparent brightness of SSOs in the unfiltered G band is also provided for selected observations.Aims: We explain the processing of SSO data, and describe the criteria we used to select the sample published in Gaia DR2. We then explore the data set to assess its quality.Methods: To exploit the main data product for the solar system in Gaia DR2, which is the epoch astrometry of asteroids, it is necessary to take into account the unusual properties of the uncertainty, as the position information is nearly one-dimensional. When this aspect is handled appropriately, an orbit fit can be obtained with post-fit residuals that are overall consistent with the a-priori error model that was used to define individual values of the astrometric uncertainty. The role of both random and systematic errors is described. The distribution of residuals allowed us to identify possible contaminants in the data set (such as stars). Photometry in the G band was compared to computed values from reference asteroid shapes and to the flux registered at the corresponding epochs by the red and blue photometers (RP and BP).Results: The overall astrometric performance is close to the expectations, with an optimal range of brightness G similar to 12 - 17. In this range, the typical transit-level accuracy is well below 1 mas. For fainter asteroids, the growing photon noise deteriorates the performance. Asteroids brighter than G similar to 12 are affected by a lower performance of the processing of their signals. The dramatic improvement brought by Gaia DR2 astrometry of SSOs is demonstrated by comparisons to the archive data and by preliminary tests on the detection of subtle non-gravitational effects.
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| 10. |
- Ryu, Y. -H., et al.
(författare)
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OGLE-2016-BLG-1190Lb : The First Spitzer Bulge Planet Lies Near the Planet/Brown-dwarf Boundary
- 2018
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Ingår i: Astronomical Journal. - : American Astronomical Society. - 0004-6256 .- 1538-3881. ; 155:1
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Tidskriftsartikel (refereegranskat)abstract
- We report the discovery of OGLE-2016-BLG-1190Lb, which is likely to be the first Spitzer microlensing planet in the Galactic bulge/ bar, an assignation that can be confirmed by two epochs of high-resolution imaging of the combined source-lens baseline object. The planet's mass, M-p = 13.4 +/- 0.9 M-J, places it right at the deuteriumburning limit, i. e., the conventional boundary between planets and brown dwarfs. Its existence raises the question of whether such objects are really planets (formed within the disks of their hosts) or failed stars (lowmass objects formed by gas fragmentation). This question may ultimately be addressed by comparing disk and bulge/bar planets, which is a goal of the Spitzer microlens program. The host is a G dwarf, M-host = 0.89. +/- 0.07 M-circle dot, and the planet has a semimajor axis a similar to 2.0 au. We use Kepler K2 Campaign 9 microlensing data to break the lens-mass degeneracy that generically impacts parallax solutions from Earth-Spitzer observations alone, which is the first successful application of this approach. The microlensing data, derived primarily from near-continuous, ultradense survey observations from OGLE, MOA, and three KMTNet telescopes, contain more orbital information than for any previous microlensing planet, but not quite enough to accurately specify the full orbit. However, these data do permit the first rigorous test of microlensing orbital-motion measurements, which are typically derived from data taken over < 1% of an orbital period.
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| 11. |
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| 12. |
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| 13. |
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| 14. |
- Hirao, Yuki, et al.
(författare)
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OGLE-2017-BLG-0406 : Spitzer Microlens Parallax Reveals Saturn-mass Planet Orbiting M-dwarf Host in the Inner Galactic Disk
- 2020
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Ingår i: Astronomical Journal. - : American Astronomical Society. - 0004-6256 .- 1538-3881. ; 160:2
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Tidskriftsartikel (refereegranskat)abstract
- We report the discovery and analysis of the planetary microlensing event OGLE-2017-BLG-0406, which was observed both from the ground and by the Spitzer satellite in a solar orbit. At high magnification, the anomaly in the light curve was densely observed by ground-based-survey and follow-up groups, and it was found to be explained by a planetary lens with a planet/host mass ratio of q = 7.0 x 10(-4) from the light-curve modeling. The ground-only and Spitzer-only data each provide very strong one-dimensional (1D) constraints on the 2D microlens parallax vector pi(E). When combined, these yield a precise measurement of pi(E) and of the masses of the host M-host = 0.56 +/- 0.07 M-circle dot and planet M-planet = 0.41 +/- 0.05 M-Jup. The system lies at a distance D-L = 5.2 +/- 0.5 kpc from the Sun toward the Galactic bulge, and the host is more likely to be a disk population star according to the kinematics of the lens. The projected separation of the planet from the host is a(perpendicular to) = 3.5 +/- 0.3 au (i.e., just over twice the snow line). The Galactic-disk kinematics are established in part from a precise measurement of the source proper motion based on OGLE-IV data. By contrast, the Gaia proper-motion measurement of the source suffers from a catastrophic 10 sigma error.
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| 15. |
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| 16. |
- Udalski, A., et al.
(författare)
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OGLE-2017-BLG-1434Lb : Eighth q < 1 x 10(-4) Mass-Ratio Microlens Planet Confirms Turnover in Planet Mass-Ratio Function
- 2018
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Ingår i: Acta Astronomica. - 0001-5237. ; 68:1, s. 1-42
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Tidskriftsartikel (refereegranskat)abstract
- We report the discovery of a cold Super-Earth planet (m(p) = 4.4 +/- 0.5 M-circle plus) orbiting a low-mass (M = 0.23 +/- 0.03 M-circle dot) M dwarf at projected separation a(perpendicular to) l = 1.18 +/- 0.10 a.u., i.e., about 1.9 times the distance the snow line. The system is quite nearby for a microlensing planet, D-L = 0.86 +/- 0.09 kpc. Indeed, it was the large lens-source relative parallax pi(rel) = 1.0 mas (combined with the low mass M) that gave rise to the large, and thus well-measured, microlens parallax pi(E) proportional to (pi(rel)/M)(1)(/2) that enabled these precise measurements. OGLE-2017-BLG-1434Lb is the eighth microlensing planet with planet-host mass ratio q < 1 x 10(-4). We apply a new planet-detection sensitivity method, which is a variant of V/V-max, to seven of these eight planets to derive the mass-ratio function in this regime. We find dN/ d lnq proportional to q(P) , with p =1.05(-0.68)(+0.78), which confirms the turnover in the mass function found by Suzuki et al. relative to the power law of opposite sign n = -0.93 +/- 0.13 at higher mass ratios q greater than or similar to 2 x 10(-4). We combine our result with that of Suzuki et al. to obtain p = 0.73(-0.34)(+0.42.)
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| 17. |
- Alosaimi, Abdullah N., et al.
(författare)
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Factors associated with female genital cutting in Yemen and its policy implications
- 2019
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Ingår i: Midwifery. - : Elsevier BV. - 0266-6138 .- 1532-3099. ; 74, s. 99-106
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Tidskriftsartikel (refereegranskat)abstract
- Background:A tremendous number of girls in Yemen are still subjected to female genital cutting (FGC), which carries an increased risk of health complications and violates children's rights. This study describes the prevalence of FGC in four Yemeni provinces and investigates the determinants of FGC.Methods: We analyzed data from women aged 15 to 49 years who responded to a sub-national household survey conducted in six rural districts of four Yemeni provinces in 2008-2009. Logistic regression was used to estimate the association between individual and household socioeconomic factors and FGC practices and attitudes.Results:The prevalence of women's FGC was 48% while daughters' FGC was 34%. Almost 45.8% of the women surveyed believe the FGC practice should discontinue. Higher odds of FGC practice and positive attitude towards it were associated with older age, family marriage, and lower tertiles of wealth and education indices. Early marriage was also associated with increased odds of FGC practice (p < 0.01).Conclusions:Socioeconomic indices and other individual factors associated with FGC are differing and complex. Younger generations of women are more likely to not have FGC and to express negative attitudes towards the tradition. Appropriate strategies to invest in girls' education and women's empowerment with effective engagement of religious and community leaders might support the change of attitudes and practice of FGC in the younger generation.
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| 18. |
- Barredo, José I., et al.
(författare)
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Mapping and assessment of forest ecosystems and their services : Applications and guidance for decision making in the framework of MAES
- 2015
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- The aim of this report is to illustrate by means of a series of case studies the implementation of mapping and assessment of forest ecosystem services in different contexts and geographical levels. Methodological aspects, data issues, approaches, limitations, gaps and further steps for improvement are analysed for providing good practices and decision making guidance. The EU initiative on Mappingand Assessment of Ecosystems and their Services (MAES), with the support of all Member States, contributes to improve the knowledge on ecosystem services. MAES is one of the building-block initiatives supporting the EU Biodiversity Strategy to 2020.
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| 19. |
- Borg, K. I., et al.
(författare)
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Force on a spinning sphere moving in a rarefied gas
- 2003
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Ingår i: Physics of fluids. - : AIP Publishing. - 1070-6631 .- 1089-7666. ; 15:3, s. 736-741
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Tidskriftsartikel (refereegranskat)abstract
- The force acting on a spinning sphere moving in a rarefied gas is calculated. It is found to have three contributions with different directions. The transversal contribution is of opposite direction compared to the so-called Magnus force normally exerted on a sphere by a dense gas. It is given by F=-alpha(tau)xi2/3piR(3)mnomegaxv, where alpha(tau) is the accommodation coefficient of tangential momentum, R is the radius of the sphere, m is the mass of a gas molecule, n is the number density of the surrounding gas, omega is the angular velocity, and v is the velocity of the center of the sphere relative to the gas. The dimensionless factor xi is close to unity, but depends on omega and kappa, the heat conductivity of the body.
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| 20. |
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| 21. |
- Boushel, R, et al.
(författare)
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Editorial
- 2015
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Ingår i: Scandinavian journal of medicine & science in sports. - : Wiley. - 1600-0838 .- 0905-7188. ; 25 Suppl 4, s. 1-6
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Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)
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| 22. |
- Cnossen, Maryse C., et al.
(författare)
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Variation in monitoring and treatment policies for intracranial hypertension in traumatic brain injury : a survey in 66 neurotrauma centers participating in the CENTER-TBI study
- 2017
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Ingår i: Critical Care. - : Springer. - 1364-8535 .- 1466-609X. ; 21:1
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: No definitive evidence exists on how intracranial hypertension should be treated in patients with traumatic brain injury (TBI). It is therefore likely that centers and practitioners individually balance potential benefits and risks of different intracranial pressure (ICP) management strategies, resulting in practice variation. The aim of this study was to examine variation in monitoring and treatment policies for intracranial hypertension in patients with TBI.METHODS: A 29-item survey on ICP monitoring and treatment was developed on the basis of literature and expert opinion, and it was pilot-tested in 16 centers. The questionnaire was sent to 68 neurotrauma centers participating in the Collaborative European Neurotrauma Effectiveness Research in Traumatic Brain Injury (CENTER-TBI) study.RESULTS: The survey was completed by 66 centers (97% response rate). Centers were mainly academic hospitals (n = 60, 91%) and designated level I trauma centers (n = 44, 67%). The Brain Trauma Foundation guidelines were used in 49 (74%) centers. Approximately 90% of the participants (n = 58) indicated placing an ICP monitor in patients with severe TBI and computed tomographic abnormalities. There was no consensus on other indications or on peri-insertion precautions. We found wide variation in the use of first- and second-tier treatments for elevated ICP. Approximately half of the centers were classified as using a relatively aggressive approach to ICP monitoring and treatment (n = 32, 48%), whereas the others were considered more conservative (n = 34, 52%).CONCLUSIONS: Substantial variation was found regarding monitoring and treatment policies in patients with TBI and intracranial hypertension. The results of this survey indicate a lack of consensus between European neurotrauma centers and provide an opportunity and necessity for comparative effectiveness research.
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| 26. |
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| 27. |
- Eliman, A., et al.
(författare)
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Totalparenteral nutrition after surgery rapidly increases serum leptin levels
- 2001
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Ingår i: European Journal of Endocrinology. - Bristol, NQ, USA : Bioscientifica. - 0804-4643 .- 1479-683X. ; 144:2, s. 123-128
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Tidskriftsartikel (refereegranskat)abstract
- Objective: In humans, leptin is regulated by long-term changes in energy intake. However, short-term regulation of serum leptin by nutrients has been difficult to show. The aim of this study was to investigate whether short periods of fasting and stress sensitise the leptin response to nutrients.Subjects and experimental protocol: Fourteen patients of normal weight undergoing elective open cholecystectomy were randomised into two groups. One group received saline infusion during surgery and for 24 h postoperatively. The other group also received saline during the surgical procedure, but total parenteral (TPN) was started immediately after surgery. Blood samples were drawn before as well as 2, 4, 8, 16, and 24 h after the start of surgery to determine the serum levels of leptin and other hormones.Results: Postoperative TPN induced a significant rise in serum leptin within 6 h, reaching a more than fourfold increase within 14 h (P < 0.001). Serum glucose and insulin levels increased within 2 h. Growth hormone and IGF-1 serum levels also increased significantly in the group receiving TPN. Serum cortisol levels increased postoperatively in both groups, which may explain why no significant reduction in serum leptin was observed in the group receiving saline. Free tri-iodothyronine (T3) decreased in both groups, while catecholamines were similar in the groups.Conclusion: During fasting and surgical stress, nutrients rapidly increased the serum leptin levels in humans in a manner similar to that previously reported in rodents. This may be mediated by increases in serum glucose, insulin and cortisol.
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| 28. |
- Essen, Johan von, et al.
(författare)
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Landsbygdens civilsamhällen som bärare av resurser
- 2022
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Ingår i: Landsbygdernas och de mindre orternas civilsamhällen. - Uppsala : Sveriges Lantbruksuniversitet. - 9789185735624 ; , s. 67-80
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Bokkapitel (övrigt vetenskapligt/konstnärligt)
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| 29. |
- Fischer, Alexander W., et al.
(författare)
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No insulating effect of obesity
- 2016
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Ingår i: American Journal of Physiology. Endocrinology and Metabolism. - : American Physiological Society. - 0193-1849 .- 1522-1555. ; 311:1, s. e202-e213
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Tidskriftsartikel (refereegranskat)abstract
- The development of obesity may be aggravated if obesity itself insulates against heat loss and thus diminishes the amount of food burnt for body temperature control. This would be particularly important under normal laboratory conditions where mice experience a chronic cold stress (at approximate to 20 degrees C). We used Scholander plots (energy expenditure plotted against ambient temperature) to examine the insulation (thermal conductance) of mice, defined as the inverse of the slope of the Scholander curve at subthermoneutral temperatures. We verified the method by demonstrating that shaved mice possessed only half the insulation of non-shaved mice. We examined a series of obesity models [mice fed high-fat diets and kept at different temperatures, classical diet-induced obese mice, ob/ob mice, and obesity-prone (C57BL/6) vs. obesity-resistant (129S)mice]. We found that neither acclimation temperature nor any kind or degree of obesity affected the thermal insulation of the mice when analyzed at the whole mouse level or as energy expenditure per lean weight. Calculation per body weight erroneously implied increased insulation in obese mice. We conclude that, in contrast to what would be expected, obesity of any kind does not increase thermal insulation in mice, and therefore, it does not in itself aggravate the development of obesity. It may be discussed as to what degree of effect excess adipose tissue has on insulation in humans and especially whether significant metabolic effects are associated with insulation in humans.
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| 30. |
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| 31. |
- Huijben, Jilske A., et al.
(författare)
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Development of a quality indicator set to measure and improve quality of ICU care for patients with traumatic brain injury
- 2019
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Ingår i: Critical Care. - : BioMed Central. - 1364-8535 .- 1466-609X. ; 23
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Tidskriftsartikel (refereegranskat)abstract
- Background: We aimed to develop a set of quality indicators for patients with traumatic brain injury (TBI) in intensive care units (ICUs) across Europe and to explore barriers and facilitators for implementation of these quality indicators.Methods: A preliminary list of 66 quality indicators was developed, based on current guidelines, existing practice variation, and clinical expertise in TBI management at the ICU. Eight TBI experts of the Advisory Committee preselected the quality indicators during a first Delphi round. A larger Europe-wide expert panel was recruited for the next two Delphi rounds. Quality indicator definitions were evaluated on four criteria: validity (better performance on the indicator reflects better processes of care and leads to better patient outcome), feasibility (data are available or easy to obtain), discriminability (variability in clinical practice), and actionability (professionals can act based on the indicator). Experts scored indicators on a 5-point Likert scale delivered by an electronic survey tool.Results. The expert panel consisted of 50 experts from 18 countries across Europe, mostly intensivists (N=24, 48%) and neurosurgeons (N=7, 14%). Experts agreed on a final set of 42 indicators to assess quality of ICU care: 17 structure indicators, 16 process indicators, and 9 outcome indicators. Experts are motivated to implement this finally proposed set (N=49, 98%) and indicated routine measurement in registries (N=41, 82%), benchmarking (N=42, 84%), and quality improvement programs (N=41, 82%) as future steps. Administrative burden was indicated as the most important barrier for implementation of the indicator set (N=48, 98%).Conclusions: This Delphi consensus study gives insight in which quality indicators have the potential to improve quality of TBI care at European ICUs. The proposed quality indicator set is recommended to be used across Europe for registry purposes to gain insight in current ICU practices and outcomes of patients with TBI. This indicator set may become an important tool to support benchmarking and quality improvement programs for patients with TBI in the future.
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| 32. |
- Jaunsen, Andreas O., et al.
(författare)
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Nordic FAIR Data Collaboration Opportunities
- 2021
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Rapport (refereegranskat)abstract
- Executive summaryIn September 2020 the NeIC Director and board initiated a working group on FAIR collaborationopportunities in the Nordics. This came in the wake of the data tsunami era and the realisationthat machine learning and connected data will become of crucial importance to society andscience. Furthermore, the findings of the EOSC-Nordic project show that the FAIR uptake in theregion is slow and a majority of data repositories are not FAIR, while only a small fractionmeasures up to the available FAIR metrics. Sharing publicly-funded data in a meaningful,reusable way must become part of the normative behaviour in order to nurture data-drivensciences. By enabling data capabilities we are facilitating interdisciplinary data reuse, along withinformation and knowledge exchange. A key objective is data integration, where concepts andproperties, and the relationships between them are linked, forming knowledge graphs andproviding an opportunity to provide insight (new knowledge) from the multitude of relations andpatterns.Although FAIR awareness is growing and there is an appreciation of the Open Science visionamong researchers and support staff, a small survey conducted by the working group confirmssome challenges that are contradictory to the Open Science (OS) movement and contribute toconfusion and status quo when it comes to implementing FAIR. If we are serious aboutembracing OS and the implementation of the FAIR principles it is necessary to ensure that allelements pull in the same direction (this includes infrastructure, skills and services to policiesand incentives). Data stewardship is gradually becoming part of the researcher workflow insome organisations, institutions and departments. Professionalising this crucial support is key tosucceeding in a swift and effective transition to sharing discoverable, accessible and reusabledata. The working group finds that coordinating tasks such as raising awareness, training andskills development and developing common tools and services for research data management(RDM) can contribute to strengthen the momentum of FAIR uptake and better utilise resources,skills and tools across the Nordics. A Nordic coordination office may be one way to orchestratea common strategy on working towards the realisation of the Open Science vision.
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| 33. |
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| 34. |
- Korlén, S., et al.
(författare)
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Leaders as intermediates between economic incentive models and professional motivation
- 2018
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Ingår i: Läkartidningen. - : Swedish Medical Association. - 0023-7205 .- 1652-7518. ; 115:22-23
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Tidskriftsartikel (refereegranskat)abstract
- The application of economic incentives to providers in health care governance is debated. Advocates argue that it drives efficiency and improvement, opponents claim that it leads to unintended consequences for patients and professionals. Research shows that incentives can increase well-defined activities and targets, but there is a lack of substantial evidence that applications in health care lead to desired outcomes. The motivational literature acknowledges internal sources of motivation as important determinants of behavior, and the literature about professions suggests that professional values of serving patient needs is a key motivator. The management literature identifies the important role of leaders in aligning external demands and rewards to staff preferences, using their own management and leadership skills. Findings in health services research confirm the vital role of leaders for successful implementation and improvement work. In sum, internal motivators and the role of leaders are important to acknowledge also when understanding how economic governance models are put into practice. Our recently published qualitative case study provides empirical examples of how clinical leaders function as intermediaries between a local care choice model, including financial incentives, and the motivation of staff. The strategies deployed by the leaders aimed to align the economic logics of the model to the professional focus on increasing patient value. The main conclusion from these empirical examples, as well as previous research, is that health care managers play a key role in aligning economic incentive models with professional values and in translating such models in to feasible tasks related to the provision of high quality care.
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| 35. |
- Korlén, S., et al.
(författare)
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Managerial strategies to make incentives meaningful and motivating
- 2017
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Ingår i: Journal of Health Organization & Management. - : Emerald Group Publishing Ltd.. - 1477-7266 .- 1758-7247. ; 31:2, s. 126-141
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Tidskriftsartikel (refereegranskat)abstract
- Purpose: Policy makers are applying market-inspired competition and financial incentives to drive efficiency in healthcare. However, a lack of knowledge exists about the process whereby incentives are filtered through organizations to influence staff motivation, and the key role of managers is often overlooked. The purpose of this paper is to explore the strategies managers use as intermediaries between financial incentives and the individual motivation of staff. The authors use empirical data from a local case in Swedish specialized care. Design/methodology/approach: The authors conducted an exploratory qualitative case study of a patient-choice reform, including financial incentives, in specialized orthopedics in Sweden. In total, 17 interviews were conducted with professionals in managerial positions, representing six healthcare providers. A hypo-deductive, thematic approach was used to analyze the data. Findings: The results show that managers applied alignment strategies to make the incentive model motivating for staff. The managers’ strategies are characterized by attempts to align external rewards with professional values based on their contextual and practical knowledge. Managers occasionally overruled the financial logic of the model to safeguard patient needs and expressed an interest in having a closer dialogue with policy makers about improvements. Originality/value: Externally imposed incentives do not automatically motivate healthcare staff. Managers in healthcare play key roles as intermediaries by aligning external rewards with professional values. Managers’ multiple perspectives on healthcare practices and professional culture can also be utilized to improve policy and as a source of knowledge in partnership with policy makers.
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| 36. |
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Landsbygdernas och de mindre orternas civilsamhällen
- 2022
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Samlingsverk (redaktörskap) (övrigt vetenskapligt/konstnärligt)abstract
- Denna rapport introducerar det forskningsfält som uppstår när landsbygdsforskning och civilsamhällesforskning möts. Texterna i rapporten presenterades vid en konferens som genomfördes 2021 av en grupp forskare som är verksamma inom civilsamhällesforskning och landsbygdsforskning. Som framgår av konferensens titel, ”Landsbygdernas och de mindre orternas civilsamhällen”, skulle den ge möjlighet för dessa två forskningsområden att mötas och fördjupa varandra. Rapporten är tänkt som en ingång till aktuell forskning på detta tema och vi tror den kan vara intressant läsning för både aktiva inom civilsamhällets organisationer och verksamma inom myndigheter, regioner och kommuner som relaterar till landsbygdernas civilsamhälle i sitt arbete.Rapporten inleds med ett kapitel som kortfattat och översiktligt beskriver hur civilsamhällesforskning och landsbygdsforskning växt fram och diskuterar behovet av forskning som sätter fokus på landsbygdernas och de mindre orternas civilsamhällen. De inkluderade kapitlen presenterar forskning där landsbygdernas civilsamhällen studerats med olika metoder och ur flera olika perspektiv.I den första delen av rapporten presenteras forskning som beskriver skillnader och likheter i civilsamhällesengagemang mellan städer och landsbygd i Sverige, behandlar hur tillgång till service också kan påverka tillit till institutioner och diskuterar betydelsen av känslor i relation till civilsamhällesengagemang och samhällsutveckling. Vidare presenteras en övergripande bild av kunskapsläget om social innovation som svar på landsbygdens samhällsutmaningar, med särskilt fokus på civilsamhällets roll och samverkan med andra samhällsaktörer.Utifrån en studie av civilsamhällesprojekt finansierade med offentliga medel diskuteras också hur de ekonomiska bidragsresurserna omvandlas till immateriella resurser till nytta för lokaldesamhället. Rapporten innehåller också kapitel som diskuterar civilsamhällets alternativa bildningsvägar som utgår från platsers egna premisser, sociala rörelser för hållbarhet på den svensk-samiska landsbygden samt ett kapitel som diskuterar hur medborgarskapet omformas när boende i landsbygder och mindre orter i större utsträckning behöver förlita sig på civilsamhällets lösningar för att få tillgång till vardaglig service och grundläggande infrastruktur.
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| 37. |
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| 38. |
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| 39. |
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| 40. |
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| 41. |
- van Essen, Thomas A, et al.
(författare)
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Comparative effectiveness of decompressive craniectomy versus craniotomy for traumatic acute subdural hematoma (CENTER-TBI) : an observational cohort study
- 2023
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Ingår i: eClinicalMedicine. - : Elsevier. - 2589-5370. ; 63
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: Limited evidence existed on the comparative effectiveness of decompressive craniectomy (DC) versus craniotomy for evacuation of traumatic acute subdural hematoma (ASDH) until the recently published randomised clinical trial RESCUE-ASDH. In this study, that ran concurrently, we aimed to determine current practice patterns and compare outcomes of primary DC versus craniotomy.METHODS: We conducted an analysis of centre treatment preference within the prospective, multicentre, observational Collaborative European NeuroTrauma Effectiveness Research in Traumatic Brain Injury (known as CENTER-TBI) and NeuroTraumatology Quality Registry (known as Net-QuRe) studies, which enrolled patients throughout Europe and Israel (2014-2020). We included patients with an ASDH who underwent acute neurosurgical evacuation. Patients with severe pre-existing neurological disorders were excluded. In an instrumental variable analysis, we compared outcomes between centres according to treatment preference, measured by the case-mix adjusted proportion DC per centre. The primary outcome was functional outcome rated by the 6-months Glasgow Outcome Scale Extended, estimated with ordinal regression as a common odds ratio (OR), adjusted for prespecified confounders. Variation in centre preference was quantified with the median odds ratio (MOR). CENTER-TBI is registered with ClinicalTrials.gov, number NCT02210221, and the Resource Identification Portal (Research Resource Identifier SCR_015582).FINDINGS: Between December 19, 2014 and December 17, 2017, 4559 patients with traumatic brain injury were enrolled in CENTER-TBI of whom 336 (7%) underwent acute surgery for ASDH evacuation; 91 (27%) underwent DC and 245 (63%) craniotomy. The proportion primary DC within total acute surgery cases ranged from 6 to 67% with an interquartile range (IQR) of 12-26% among 46 centres; the odds of receiving a DC for prognostically similar patients in one centre versus another randomly selected centre were trebled (adjusted median odds ratio 2.7, p < 0.0001). Higher centre preference for DC over craniotomy was not associated with better functional outcome (adjusted common odds ratio (OR) per 14% [IQR increase] more DC in a centre = 0.9 [95% CI 0.7-1.1], n = 200). Primary DC was associated with more follow-on surgeries and complications [secondary cranial surgery 27% vs. 18%; shunts 11 vs. 5%]; and similar odds of in-hospital mortality (adjusted OR per 14% IQR more primary DC 1.3 [95% CI (1.0-3.4), n = 200]).INTERPRETATION: We found substantial practice variation in the employment of DC over craniotomy for ASDH. This variation in treatment strategy did not result in different functional outcome. These findings suggest that primary DC should be restricted to salvageable patients in whom immediate replacement of the bone flap is not possible due to intraoperative brain swelling.FUNDING: Hersenstichting Nederland for the Dutch NeuroTraumatology Quality Registry and the European Union Seventh Framework Program.
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| 42. |
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| 43. |
- van Essen, Thomas A., et al.
(författare)
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Surgery versus conservative treatment for traumatic acute subdural haematoma : a prospective, multicentre, observational, comparative effectiveness study
- 2022
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Ingår i: Lancet Neurology. - : Elsevier. - 1474-4422 .- 1474-4465. ; 21:7, s. 620-631
-
Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: Despite being well established, acute surgery in traumatic acute subdural haematoma is based on low-grade evidence. We aimed to compare the effectiveness of a strategy preferring acute surgical evacuation with one preferring initial conservative treatment in acute subdural haematoma.METHODS: We did a prospective, observational, comparative effectiveness study using data from participants enrolled in the Collaborative European Neurotrauma Effectiveness Research in Traumatic Brain Injury (CENTER-TBI) cohort. We included patients with no pre-existing severe neurological disorders who presented with acute subdural haematoma within 24 h of traumatic brain injury. Using an instrumental variable analysis, we compared outcomes between centres according to treatment preference for acute subdural haematoma (acute surgical evacuation or initial conservative treatment), measured by the case-mix-adjusted percentage of acute surgery per centre. The primary endpoint was functional outcome at 6 months as rated with the Glasgow Outcome Scale Extended, which was estimated with ordinal regression as a common odds ratio (OR) and adjusted for prespecified confounders. Variation in centre preference was quantified with the median OR (MOR). CENTER-TBI is registered with ClinicalTrials.gov, number NCT02210221, and the Resource Identification Portal (Research Resource Identifier SCR_015582).FINDINGS: Between Dec 19, 2014 and Dec 17, 2017, 4559 patients with traumatic brain injury were enrolled in CENTER-TBI, of whom 1407 (31%) presented with acute subdural haematoma and were included in our study. Acute surgical evacuation was done in 336 (24%) patients, by craniotomy in 245 (73%) of those patients and by decompressive craniectomy in 91 (27%). Delayed decompressive craniectomy or craniotomy after initial conservative treatment (n=982) occurred in 107 (11%) patients. The percentage of patients who underwent acute surgery ranged from 5·6% to 51·5% (IQR 12·3-35·9) between centres, with a two-times higher probability of receiving acute surgery for an identical patient in one centre versus another centre at random (adjusted MOR for acute surgery 1·8; p<0·0001]). Centre preference for acute surgery over initial conservative treatment was not associated with improvements in functional outcome (common OR per 23·6% [IQR increase] more acute surgery in a centre 0·92, 95% CI 0·77-1·09).INTERPRETATION: Our findings show that treatment for patients with acute subdural haematoma with similar characteristics differed depending on the treating centre, because of variation in the preferred approach. A treatment strategy preferring an aggressive approach of acute surgical evacuation over initial conservative treatment was not associated with better functional outcome. Therefore, in a patient with acute subdural haematoma for whom a neurosurgeon sees no clear superiority for acute surgery over conservative treatment, initial conservative treatment might be considered.FUNDING: The Hersenstichting Nederland (also known as the Dutch Brain Foundation), the European Commission Seventh Framework Programme, the Hannelore Kohl Stiftung (Germany), OneMind (USA), Integra LifeSciences Corporation (USA), and NeuroTrauma Sciences (USA).
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| 44. |
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| 45. |
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| 46. |
- von Essen, Louise, et al.
(författare)
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Important aspects of care and assistance for parents of children, 0-18 years of age, on or off treatment for cancer : Parent and nurse perceptions.
- 2001
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Ingår i: European Journal of Oncology Nursing. - : Elsevier BV. - 1462-3889 .- 1532-2122. ; 5:4, s. 254-264
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Tidskriftsartikel (refereegranskat)abstract
- Important aspects of care and assistance for parents of children (0–18 years) diagnosed with cancer were investigated. Parents (N=114) and nurses (N=121) were asked the following questions: ‘What caring aspects are important for you/the parent to feel cared for?’ and ‘What help, if any, do you/the parent need outside the hospital?’ Nurses were asked to answer for a certain parent. Data were analyzed by content analysis. The following aspects of care were identified: accessible care, clinical competence, continuity, emotional support, information, participation in care, participation in decision making, physical ambience, shift in parenting roles, social competence, temporary assistance, own child is well cared for, and time. Most parents mentioned the importance of social competence and information, most nurses mentioned the importance of information and emotional support. The following aspects of assistance were identified: accessible care, emotional support, financial support, instrumental support, and support to live a normal family/social life. A third of the parents and a fourth of the nurses were of the opinion that the parent did not need any assistance. Most parents who mentioned a need of assistance mentioned a need for emotional and instrumental support. Most nurses mentioned a parental need for emotional support and accessible care.
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| 47. |
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| 48. |
- Åberg, Pelle, Docent i statsvetenskap, 1977-, et al.
(författare)
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Folkbildning i landsbygder : Om folkbildningens betydelser för människor och lokalsamhällen i svenska landsbygder
- 2024
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- I rapporten Folkbildning i landsbygder undersöks folkbildningens betydelse för människor och lokalsamhällen i tre utvalda svenska landsbygder. Vilka betydelser har studieförbund och folkhögskolor som mötesplatser och lokala offentligheter? Som infrastrukturer för lokalt samhällsengagemang? För lokal kompetensutveckling? Eller för det lokala kulturutbudet?Rapportens avslutande analys handlar om de avvägningar som studieförbundens och folkhögskolornas anställda gör mellan de ideal och riktlinjer som styr folkbildningen, och de behov som präglar det lokalsamhälle som de är verksamma i.
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