| 1. |
- de Jong, R. S., et al.
(författare)
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4MOST : Project overview and information for the First Call for Proposals
- 2019
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Ingår i: The Messenger. - : European Southern Observatory. - 0722-6691. ; 175, s. 3-11
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Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)abstract
- We introduce the 4-metre Multi-Object Spectroscopic Telescope (4MOST), a new high-multiplex, wide-field spectroscopic survey facility under development for the four-metre-class Visible and Infrared Survey Telescope for Astronomy (VISTA) at Paranal. Its key specifications are: a large field of view (FoV) of 4.2 square degrees and a high multiplex capability, with 1624 fibres feeding two low-resolution spectrographs (R = λ/Δλ ~ 6500), and 812 fibres transferring light to the high-resolution spectrograph (R ~ 20 000). After a description of the instrument and its expected performance, a short overview is given of its operational scheme and planned 4MOST Consortium science; these aspects are covered in more detail in other articles in this edition of The Messenger. Finally, the processes, schedules, and policies concerning the selection of ESO Community Surveys are presented, commencing with a singular opportunity to submit Letters of Intent for Public Surveys during the first five years of 4MOST operations.
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| 2. |
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| 3. |
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| 4. |
- Zhang, Y., et al.
(författare)
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Dark Energy Surveyed Year 1 results : calibration of cluster mis-centring in the redMaPPer catalogues
- 2019
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Ingår i: Monthly notices of the Royal Astronomical Society. - : OXFORD UNIV PRESS. - 0035-8711 .- 1365-2966. ; 487:2, s. 2578-2593
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Tidskriftsartikel (refereegranskat)abstract
- The centre determination of a galaxy cluster from an optical cluster finding algorithm can be offset from theoretical prescriptions or N-body definitions of its host halo centre. These offsets impact the recovered cluster statistics, affecting both richness measurements and the weak lensing shear profile around the clusters. This paper models the centring performance of the redMaPPer cluster finding algorithm using archival X-ray observations of redMaPPer-selected clusters. Assuming the X-ray emission peaks as the fiducial halo centres, and through analysing their offsets to the redMaPPer centres, we find that similar to 75 +/- 8 per cent of the redMaPPer clusters are well centred and the mis-centred offset follows a Gamma distribution in normalized, projected distance. These mis-centring offsets cause a systematic underestimation of cluster richness relative to the well-centred clusters, for which we propose a descriptive model. Our results enable the DES Y1 cluster cosmology analysis by characterizing the necessary corrections to both the weak lensing and richness abundance functions of the DES Y1 redMaPPer cluster catalogue.
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| 5. |
- Contarini, S., et al.
(författare)
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Euclid : cosmological forecasts from the void size function
- 2022
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Ingår i: Astronomy and Astrophysics. - : EDP Sciences. - 0004-6361 .- 1432-0746. ; 667
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Tidskriftsartikel (refereegranskat)abstract
- The Euclid mission - with its spectroscopic galaxy survey covering a sky area over 15 000 deg(2) in the redshift range 0.9 < z < 1.8 - will provide a sample of tens of thousands of cosmic voids. This paper thoroughly explores for the first time the constraining power of the void size function on the properties of dark energy (DE) from a survey mock catalogue, the official Euclid Flagship simulation. We identified voids in the Flagship light-cone, which closely matches the features of the upcoming Euclid spectroscopic data set. We modelled the void size function considering a state-of-the art methodology: we relied on the volume-conserving (Vdn) model, a modification of the popular Sheth & van de Weygaert model for void number counts, extended by means of a linear function of the large-scale galaxy bias. We found an excellent agreement between model predictions and measured mock void number counts. We computed updated forecasts for the Euclid mission on DE from the void size function and provided reliable void number estimates to serve as a basis for further forecasts of cosmological applications using voids. We analysed two different cosmological models for DE: the first described by a constant DE equation of state parameter, w, and the second by a dynamic equation of state with coefficients w(0) and w(a). We forecast 1 sigma errors on w lower than 10% and we estimated an expected figure of merit (FoM) for the dynamical DE scenario FoM(w0,wa) = 17 when considering only the neutrino mass as additional free parameter of the model. The analysis is based on conservative assumptions to ensure full robustness, and is a pathfinder for future enhancements of the technique. Our results showcase the impressive constraining power of the void size function from the Euclid spectroscopic sample, both as a stand-alone probe, and to be combined with other Euclid cosmological probes.
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| 6. |
- Farahi, A., et al.
(författare)
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Mass variance from archival X-ray properties of Dark Energy Survey Year-1 galaxy clusters
- 2019
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Ingår i: Monthly notices of the Royal Astronomical Society. - : OXFORD UNIV PRESS. - 0035-8711 .- 1365-2966. ; 490:3, s. 3341-3354
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Tidskriftsartikel (refereegranskat)abstract
- Using archival X-ray observations and a lognormal population model, we estimate constraints on the intrinsic scatter in halo mass at fixed optical richness for a galaxy cluster sample identified in Dark Energy Survey Year-One (DES-Y1) data with the redMaPPer algorithm. We examine the scaling behaviour of X-ray temperatures, T-X, with optical richness, lambda(RM), for clusters in the redshift range 0.2 < z < 0.7. X-ray temperatures are obtained from Chandra and XMM observations for 58 and 110 redMaPPer systems, respectively. Despite non-uniform sky coverage, the T-X measurements are > 50 per cent complete for clusters with lambda(RM) > 130. Regression analysis on the two samples produces consistent posterior scaling parameters, from which we derive a combined constraint on the residual scatter, sigma(ln) (T) (vertical bar) (lambda) = 0.275 +/- 0.019. Joined with constraints for T-X scaling with halo mass from the Weighing the Giants program and richness-temperature covariance estimates from the LoCuSS sample, we derive the richness-conditioned scatter in mass, sigma(ln) (M) (vertical bar) (lambda) = 0.30 +/- 0.04((stat)) +/- 0.09((sys)), at an optical richness of approximately 100. Uncertainties in external parameters, particularly the slope and variance of the T-X-mass relation and the covariance of T-X and lambda(RM) at fixed mass, dominate the systematic error. The 95 per cent confidence region from joint sample analysis is relatively broad, sigma(ln) (M) (vertical bar) (lambda) is an element of [0.14, 0.55], or a factor 10 in variance.
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| 7. |
- Frasinski, L. J., et al.
(författare)
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Dynamics of Hollow Atom Formation in Intense X-Ray Pulses Probed by Partial Covariance Mapping
- 2013
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Ingår i: Physical Review Letters. - 0031-9007 .- 1079-7114. ; 111:7, s. 073002-
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Tidskriftsartikel (refereegranskat)abstract
- When exposed to ultraintense x-radiation sources such as free electron lasers (FELs) the innermost electronic shell can efficiently be emptied, creating a transient hollow atom or molecule. Understanding the femtosecond dynamics of such systems is fundamental to achieving atomic resolution in flash diffraction imaging of noncrystallized complex biological samples. We demonstrate the capacity of a correlation method called partial covariance mapping'' to probe the electron dynamics of neon atoms exposed to intense 8 fs pulses of 1062 eV photons. A complete picture of ionization processes competing in hollow atom formation and decay is visualized with unprecedented ease and the map reveals hitherto unobserved nonlinear sequences of photoionization and Auger events. The technique is particularly well suited to the high counting rate inherent in FEL experiments.
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| 8. |
- Hamaus, N., et al.
(författare)
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Euclid : Forecasts from redshift-space distortions and the Alcock-Paczynski test with cosmic voids
- 2022
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Ingår i: Astronomy and Astrophysics. - : EDP Sciences. - 0004-6361 .- 1432-0746. ; 658
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Tidskriftsartikel (refereegranskat)abstract
- Euclid is poised to survey galaxies across a cosmological volume of unprecedented size, providing observations of more than a billion objects distributed over a third of the full sky. Approximately 20 million of these galaxies will have their spectroscopy available, allowing us to map the three-dimensional large-scale structure of the Universe in great detail. This paper investigates prospects for the detection of cosmic voids therein and the unique benefit they provide for cosmological studies. In particular, we study the imprints of dynamic (redshift-space) and geometric (Alcock-Paczynski) distortions of average void shapes and their constraining power on the growth of structure and cosmological distance ratios. To this end, we made use of the Flagship mock catalog, a state-of-the-art simulation of the data expected to be observed with Euclid. We arranged the data into four adjacent redshift bins, each of which contains about 11000 voids and we estimated the stacked void-galaxy cross-correlation function in every bin. Fitting a linear-theory model to the data, we obtained constraints on f/b and DMH, where f is the linear growth rate of density fluctuations, b the galaxy bias, D-M the comoving angular diameter distance, and H the Hubble rate. In addition, we marginalized over two nuisance parameters included in our model to account for unknown systematic effects in the analysis. With this approach, Euclid will be able to reach a relative precision of about 4% on measurements of f/b and 0.5% on DMH in each redshift bin. Better modeling or calibration of the nuisance parameters may further increase this precision to 1% and 0.4%, respectively. Our results show that the exploitation of cosmic voids in Euclid will provide competitive constraints on cosmology even as a stand-alone probe. For example, the equation-of-state parameter, w, for dark energy will be measured with a precision of about 10%, consistent with previous more approximate forecasts.
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| 9. |
- Mehrtens, N., et al.
(författare)
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The XMM Cluster Survey : the halo occupation number of BOSS galaxies in X-ray clusters
- 2016
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Ingår i: Monthly notices of the Royal Astronomical Society. - : Oxford University Press (OUP). - 0035-8711 .- 1365-2966. ; 463:2, s. 1929-1943
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Tidskriftsartikel (refereegranskat)abstract
- We present a direct measurement of the mean halo occupation distribution (HOD) of galaxies taken from the eleventh data release (DR11) of the Sloan Digital Sky Survey-III Baryon Oscillation Spectroscopic Survey (BOSS). The HOD of BOSS low-redshift (LOWZ: 0.2 < z < 0.4) and Constant-Mass (CMASS: 0.43 < z < 0.7) galaxies is inferred via their association with the dark matter haloes of 174 X-ray-selected galaxy clusters drawn from the XMM Cluster Survey (XCS). Halo masses are determined for each galaxy cluster based on X-ray temperature measurements, and range between log10(M180/M⊙) = 13 and 15. Our directly measured HODs are consistent with the HOD-model fits inferred via the galaxy-clustering analyses of Parejko et al. for the BOSS LOWZ sample and White et al. for the BOSS CMASS sample. Under the simplifying assumption that the other parameters that describe the HOD hold the values measured by these authors, we have determined a best-fitting alpha-index of 0.91 ± 0.08 and 1.27−0.04+0.03" role="presentation">1.27+0.03−0.04 for the CMASS and LOWZ HOD, respectively. These alpha-index values are consistent with those measured by White et al. and Parejko et al. In summary, our study provides independent support for the HOD models assumed during the development of the BOSS mock-galaxy catalogues that have subsequently been used to derive BOSS cosmological constraints.
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| 10. |
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| 11. |
- Palmese, A., et al.
(författare)
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Stellar mass as a galaxy cluster mass proxy : application to the Dark Energy Survey redMaPPer clusters
- 2020
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Ingår i: \mnras. - : Oxford University Press (OUP). ; 493:4, s. 4591-4606
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Tidskriftsartikel (refereegranskat)abstract
- We introduce a galaxy cluster mass observable, μ⋆, based on the stellar masses of cluster members, and we present results for the Dark Energy Survey (DES) Year 1 (Y1) observations. Stellar masses are computed using a Bayesian model averaging method, and are validated for DES data using simulations and COSMOS data. We show that μ⋆ works as a promising mass proxy by comparing our predictions to X-ray measurements. We measure the X-ray temperature–μ⋆ relation for a total of 129 clusters matched between the wide-field DES Y1 redMaPPer catalogue and Chandra and XMM archival observations, spanning the redshift range 0.1 < z < 0.7. For a scaling relation that is linear in logarithmic space, we find a slope of α = 0.488 ± 0.043 and a scatter in the X-ray temperature at fixed μ⋆ of σlnTX|μ⋆=0.266+0.019−0.020 for the joint sample. By using the halo mass scaling relations of the X-ray temperature from the Weighing the Giants program, we further derive the μ⋆-conditioned scatter in mass, finding σlnM|μ⋆=0.26+0.15−0.10. These results are competitive with well-established cluster mass proxies used for cosmological analyses, showing that μ⋆ can be used as a reliable and physically motivated mass proxy to derive cosmological constraints.
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| 12. |
- Upsdell, E. W., et al.
(författare)
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The XMM cluster survey : exploring scaling relations and completeness of the dark energy survey year 3 redMaPPer cluster catalogue
- 2023
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Ingår i: Monthly notices of the Royal Astronomical Society. - : Oxford University Press (OUP). - 0035-8711 .- 1365-2966. ; 522:4, s. 5267-5290
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Tidskriftsartikel (refereegranskat)abstract
- We cross-match and compare characteristics of galaxy clusters identified in observations from two sky surveys using two completely different techniques. One sample is optically selected from the analysis of 3 years of Dark Energy Survey observations using the redMaPPer cluster detection algorithm. The second is X-ray selected from XMM observations analysed by the XMM Cluster Survey. The samples comprise a total area of 57.4 deg(2), bounded by the area of four contiguous XMM survey regions that overlap the DES footprint. We find that the X-ray-selected sample is fully matched with entries in the redMaPPer catalogue, above lambda > 20 and within 0.1 < z < 0.9. Conversely, only 38 per cent of the redMaPPer catalogue is matched to an X-ray extended source. Next, using 120 optically clusters and 184 X-ray-selected clusters, we investigate the form of the X-ray luminosity-temperature (L-X -T-X ), luminosity-richness (L-X - lambda), and temperature-richness (T-X - lambda) scaling relations. We find that the fitted forms of the L-X -T-X relations are consistent between the two selection methods and also with other studies in the literature. However, we find tentative evidence for a steepening of the slope of the relation for low richness systems in the X-ray-selected sample. When considering the scaling of richness with X-ray properties, we again find consistency in the relations (i.e. L-X - lambda and T-X - lambda) between the optical and X-ray-selected samples. This is contrary to previous similar works that find a significant increase in the scatter of the luminosity scaling relation for X-ray-selected samples compared to optically selected samples.
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| 13. |
- Zhang, Y., et al.
(författare)
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Galaxies in X-ray selected clusters and groups in Dark Energy Survey data - II. Hierarchical Bayesian modelling of the red-sequence galaxy luminosity function
- 2019
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Ingår i: Monthly notices of the Royal Astronomical Society. - : OXFORD UNIV PRESS. - 0035-8711 .- 1365-2966. ; 488:1, s. 1-17
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Tidskriftsartikel (refereegranskat)abstract
- Using similar to 100 X-ray selected clusters in the Dark Energy Survey Science Verification data, we constrain the luminosity function ( LF) of cluster red-sequence galaxies as a function of redshift. This is the first homogeneous optical/X-ray sample large enough to constrain the evolution of the LF simultaneously in redshift ( 0.1 < z < 1.05) and cluster mass ( 13.5 <= log(10)( M-200crit) similar to< 15.0). We pay particular attention to completeness issues and the detection limit of the galaxy sample. We then apply a hierarchical Bayesian model to fit the cluster galaxy LFs via a Schechter function, including its characteristic break ( m*) to a faint end power-law slope ( alpha). Our method enables us to avoid known issues in similar analyses based on stacking or binning the clusters. We find weak and statistically insignificant (similar to 1.9 sigma) evolution in the faint end slope alpha versus redshift. We also find no dependence in alpha or m* with the X-ray inferred cluster masses. However, the amplitude of the LF as a function of cluster mass is constrained to similar to 20 per cent precision. As a by-product of our algorithm, we utilize the correlation between the LF and cluster mass to provide an improved estimate of the individual cluster masses as well as the scatter in true mass given the X-ray inferred masses. This technique can be applied to a larger sample of X-ray or optically selected clusters from the Dark Energy Survey, significantly improving the sensitivity of the analysis.
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| 14. |
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| 15. |
- Sahlén, Martin, et al.
(författare)
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Experimental Verification of the Chemical Sensitivity of Two-Site Double Core-Hole States Formed by an X-Ray Free-Electron Laser
- 2012
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Ingår i: Physical Review Letters. - 0031-9007 .- 1079-7114. ; 108:15, s. 153003-
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Tidskriftsartikel (refereegranskat)abstract
- We have performed x-ray two-photon photoelectron spectroscopy using the Linac Coherent Light Source x-ray free-electron laser in order to study double core-hole (DCH) states of CO2, N2O, and N-2. The experiment verifies the theory behind the chemical sensitivity of two-site DCH states by comparing a set of small molecules with respect to the energy shift of the two-site DCH state and by extracting the relevant parameters from this shift.
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| 16. |
- Sahlén, Pelin, et al.
(författare)
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Chromatin interactions in differentiating keratinocytes reveal novel atopic dermatitis– and psoriasis-associated genes
- 2020
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Ingår i: Journal of Allergy and Clinical Immunology. - : Mosby Inc.. - 0091-6749 .- 1097-6825.
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Tidskriftsartikel (refereegranskat)abstract
- Background: Hundreds of variants associated with atopic dermatitis (AD) and psoriasis, 2 common inflammatory skin disorders, have previously been discovered through genome-wide association studies (GWASs). The majority of these variants are in noncoding regions, and their target genes remain largely unclear. Objective: We sought to understand the effects of these noncoding variants on the development of AD and psoriasis by linking them to the genes that they regulate. Methods: We constructed genomic 3-dimensional maps of human keratinocytes during differentiation by using targeted chromosome conformation capture (Capture Hi-C) targeting more than 20,000 promoters and 214 GWAS variants and combined these data with transcriptome and epigenomic data sets. We validated our results with reporter assays, clustered regularly interspaced short palindromic repeats activation, and examination of patient gene expression from previous studies. Results: We identified 118 target genes of 82 AD and psoriasis GWAS variants. Differential expression of 58 of the 118 target genes (49%) occurred in either AD or psoriatic lesions, many of which were not previously linked to any skin disease. We highlighted the genes AFG1L, CLINT1, ADO, LINC00302, and RP1-140J1.1 and provided further evidence for their potential roles in AD and psoriasis. Conclusions: Our work focused on skin barrier pathology through investigation of the interaction profile of GWAS variants during keratinocyte differentiation. We have provided a catalogue of candidate genes that could modulate the risk of AD and psoriasis. Given that only 35% of the target genes are the gene nearest to the known GWAS variants, we expect that our work will contribute to the discovery of novel pathways involved in AD and psoriasis.
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| 17. |
- Weltman, A., et al.
(författare)
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Fundamental physics with the Square Kilometre Array
- 2020
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Ingår i: Publications Astronomical Society of Australia. - : CAMBRIDGE UNIV PRESS. - 1323-3580 .- 1448-6083. ; 37
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Forskningsöversikt (refereegranskat)abstract
- The Square Kilometre Array (SKA) is a planned large radio interferometer designed to operate over a wide range of frequencies, and with an order of magnitude greater sensitivity and survey speed than any current radio telescope. The SKA will address many important topics in astronomy, ranging from planet formation to distant galaxies. However, in this work, we consider the perspective of the SKA as a facility for studying physics. We review four areas in which the SKA is expected to make major contributions to our understanding of fundamental physics: cosmic dawn and reionisation; gravity and gravitational radiation; cosmology and dark energy; and dark matter and astroparticle physics. These discussions demonstrate that the SKA will be a spectacular physics machine, which will provide many new breakthroughs and novel insights on matter, energy, and spacetime.
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| 18. |
- Zackrisson, Erik, et al.
(författare)
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Bubble mapping with the Square Kilometre Array - I. Detecting galaxies with Euclid, JWST, WFIRST, and ELT within ionized bubbles in the intergalactic medium at z > 6
- 2020
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Ingår i: Monthly notices of the Royal Astronomical Society. - : Oxford University Press (OUP). - 0035-8711 .- 1365-2966. ; 493:1, s. 855-870
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Tidskriftsartikel (refereegranskat)abstract
- The Square Kilometre Array (SKA) is expected to provide the first tomographic observations of the neutral intergalactic medium at redshifts z > 6 and pinpoint the locations of individual ionized bubbles during early stages of cosmic reionization. In scenarios where star-forming galaxies provide most of the ionizing photons required for cosmic reionization, one expects the first ionized bubbles to be centred on overdensities of such galaxies. Here, we model the properties of galaxy populations within isolated, ionized bubbles that SKA-1 should be able to resolve at z approximate to 7-10, and explore the prospects for galaxy counts within such structures with various upcoming near-infrared telescopes. We find that, for the bubbles that are within reach of SKA-1 tomography, the bubble volume is closely tied to the number of ionizing photons that have escaped from the galaxies within. In the case of galaxy-dominated reionization, galaxies are expected to turn up above the spectroscopic detection threshold of JWST and ELT in even the smallest resolvable bubbles at z <= 10. The prospects of detecting galaxies within these structures in purely photometric surveys with Euclid, WFIRST, JWST, or ELT are also discussed. While spectroscopy is preferable towards the end of reionization to provide a robust sample of bubble members, multiband imaging may be a competitive option for bubbles at z approximate to 10, due to the very small number of line-of-sight interlopers expected at these redshifts.
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| 19. |
- Acero Sanchez, Josep Ll., et al.
(författare)
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Electrochemical Genetic Profiling of Single Cancer Cells
- 2017
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Ingår i: Analytical Chemistry. - : American Chemical Society (ACS). - 0003-2700 .- 1520-6882. ; 89:6, s. 3378-3385
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Tidskriftsartikel (refereegranskat)abstract
- Recent understandings in the development and spread of cancer have led to the realization of novel single cell analysis platforms focused on circulating tumor cells (CTCs). A simple, rapid, and inexpensive analytical platform capable of providing genetic information on these rare cells is highly desirable to support clinicians and researchers alike to either support the selection or adjustment of therapy or provide fundamental insights into cell function and cancer progression mechanisms. We report on the genetic profiling of single cancer cells, exploiting a combination of multiplex ligation-dependent probe amplification (MLPA) and electrochemical detection. Cells were isolated using laser capture and lysed, and the mRNA was extracted and transcribed into DNA. Seven markers were amplified by MLPA, which allows for the simultaneous amplification of multiple targets with a single primer pair, using MLPA probes containing unique barcode sequences. Capture probes complementary to each of these barcode sequences were immobilized on a printed circuit board (PCB) manufactured electrode array and exposed to single-stranded MLPA products and subsequently to a single stranded DNA reporter probe bearing a HRP molecule, followed by substrate addition and fast electrochemical pulse amperometric detection. We present asimple, rapid, flexible, and inexpensive approach for the simultaneous quantification of multiple breast cancer related mRNA markers, with single tumor cell sensitivity.
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| 20. |
- Afshar, R., et al.
(författare)
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A micro-CT investigation of densification in pressboard due to compression
- 2023
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Ingår i: Strain. - : John Wiley & Sons. - 0039-2103 .- 1475-1305. ; 59:4
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Tidskriftsartikel (refereegranskat)abstract
- As a non-destructive inspection method, micro-computed tomography has been employed for determining local properties of a cellulose-based product, specifically pressboard. Furthermore, by utilizing the determined properties in a detailed numerical model, by means of a finite element analysis, we demonstrate a continuum anisotropic viscoelastic-viscoplastic model. Through such a combination of non-invasive experiments with accurate computations in mechanics, we attain a better understanding of materials and its structural integrity at a pre-production stage increasing the success of the first prototype. In detail, this combination of micro-computed tomography and finite element analysis improves accuracy in predicting materials response by taking into account the local material variations. Specifically, we have performed indentation tests and scanned the internal structure of the specimen for analysing the densification patterns within the material. Subsequently, we have used a developed material model for predicting the response of material to indentation. We have computed the indentation test itself by simulating the mechanical response of high-density cellulose-based materials. In the end, we have observed that pressboard, having initially a heterogeneous density distribution through the thickness, shows a shift in the densification to the more porous part after indentation. The densification maps of the simulated results are presented by comparing with the experimental results. A reasonable agreement is observed between the experimental and the simulated densifications patterns, which suggests that the proposed methodology can be used to predict densification also for other fibre-based materials during manufacturing or in service loading.
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| 21. |
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| 22. |
- Brännström, K. Jonas, et al.
(författare)
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Immediate passage comprehension and encoding of information into long-term memory in children with normal hearing : The effect of voice quality and multitalker babble noise
- 2018
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Ingår i: American Journal of Audiology. - 1059-0889. ; 27:2, s. 231-237
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Tidskriftsartikel (refereegranskat)abstract
- Purpose: This study examines how voice quality and multitalker babble noise affect immediate passage comprehension and the efficiency of information encoding into long-term memory in children with normal hearing. Method: Eighteen children (mean age = 9 years) with normal hearing participated. Immediate passage comprehension performance and delayed performance (after 5 to 8 days) were assessed for 4 listening conditions: a typical voice in quiet, a typical voice in noise, a dysphonic voice in quiet, and a dysphonic voice in noise. Results: Multitalker babble noise had a significant effect on immediate and delayed performance. This effect was more pronounced for delayed performance. No significant main effect of voice quality was seen on immediate or delayed performance. Conclusions: Multitalker babble noise impairs immediate passage comprehension and encoding of information into long-term memory for later recall in children with normal hearing. In learning situations where competing speech signals are present, background noise may reduce the prerequisites for optimal learning.
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| 23. |
- Brännström, K. Jonas, et al.
(författare)
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Passage comprehension performance in children with cochlear implants and/or hearing aids : the effects of voice quality and multi-talker babble noise in relation to executive function
- 2020
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Ingår i: Logopedics Phoniatrics Vocology. - : Informa UK Limited. - 1401-5439 .- 1651-2022. ; 45:1, s. 15-23
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Tidskriftsartikel (refereegranskat)abstract
- Purpose: Speech signal degradation such as a voice disorder presented in quiet or in combination with multi-talker babble noise could affect listening comprehension in children with hearing impairment. This study aims to investigate the effects of voice quality and multi-talker babble noise on passage comprehension in children with using cochlear implants (CIs) and/or hearing aids (HAs). It also aims to examine what role executive functioning has for passage comprehension in listening conditions with degraded signals (voice quality and multi-talker babble noise) in children using CI/HA. Methods: Twenty-three children (10 boys and 13 girls; mean age 9 years) using CI and/or HA were tested for passage comprehension in four listening conditions: a typical voice or a (hoarse) dysphonic, voice presented in quiet or in multi-talker babble noise. Results: The results show that the dysphonic voice did not affect passage comprehension in quiet or in noise. Multi-talker babble noise decreased passage comprehension compared to performance in quiet. No interactions with executive function were found. Conclusions: In conclusion, children with CI/HA seem to struggle with comprehension in poor sound environments, which in turn may reduce learning opportunities at school.
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| 24. |
- Brännström, K. Jonas, et al.
(författare)
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Perceived listening effort in children with hearing loss : listening to a dysphonic voice in quiet and in noise
- 2022
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Ingår i: Logopedics Phoniatrics Vocology. - : Informa UK Limited. - 1401-5439 .- 1651-2022. ; 47:1, s. 1-9
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Tidskriftsartikel (refereegranskat)abstract
- Aim: The present study investigates the effect of signal degradation on perceived listening effort in children with hearing loss listening in a simulated class-room context. It also examines the associations between perceived listening effort, passage comprehension performance and executive functioning. Methods: Twenty-four children (aged 06:03–13:00 years) with hearing impairment using cochlear implant (CI) and/or hearing aids (HA) participated. The children made ratings of perceived listening effort after completing an auditory passage comprehension task. All children performed the task in four different listening conditions: listening to a typical (i.e. normal) voice in quiet, to a dysphonic voice in quiet, to a typical voice in background noise and to a dysphonic voice in background noise. In addition, the children completed a task assessing executive function. Results: Both voice quality and background noise increased perceived listening effort in children with CI/HA, but no interaction with executive function was seen. Conclusion: Since increased listening effort seems to be a consequence of increased cognitive resource spending, it is likely that less resources will be available for these children not only to comprehend but also to learn in challenging listening environments such as classrooms.
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| 25. |
- Brännström, K. Jonas, et al.
(författare)
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The influence of voice quality and multi-talker babble noise on sentence processing and recall performance in school children using cochlear implant and/or hearing aids
- 2019
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Ingår i: Logopedics Phoniatrics Vocology. - : Informa UK Limited. - 1401-5439 .- 1651-2022. ; 44:2, s. 87-94
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Tidskriftsartikel (refereegranskat)abstract
- Purpose: This study examines the influence of voice quality and multi-talker babble noise on processing and storage performance in a working memory task performed by children using cochlear implants (CI) and/or hearing aids (HA). Methods: Twenty-three children with a hearing impairment using CI and/or HA participated. Age range was between 6 and 13 years. The Competing Language Processing Task (CLPT) was assessed in three listening conditions; a typical voice presented in quiet, a dysphonic voice in quiet, and a typical voice in multi-talker babble noise (signal-to-noise ratio +10 dB). Being a dual task, the CLPT consists of a sentence processing component and a recall component. The recall component constitutes the measure of working memory capacity (WMC). Higher-level executive function was assessed using Elithorn?s mazes. Results: The results showed that the dysphonic voice did not affect performance in the processing component or performance in the recall component. Multi-talker babble noise decreased performance in the recall component but not in the processing component. Higher-level executive function was not significantly related to performance in any component. Conclusions: The findings indicate that multi-talker babble noise, but not a dysphonic voice quality, seems to put strain on WMC in children using CI and/or HA. AbbreviationsCLPT competing language processing taskISTS international speech test signalSLP speech and language pathologistsWMC working memory capacity.
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| 26. |
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| 27. |
- Edfors, Robert, et al.
(författare)
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Outcomes in patients treated with ticagrelor versus clopidogrel after acute myocardial infarction stratified by renal function
- 2018
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Ingår i: Heart. - : BMJ Publishing Group Ltd. - 1355-6037 .- 1468-201X. ; 104:19, s. 1575-1582
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Tidskriftsartikel (refereegranskat)abstract
- Objectives We aimed to analyse outcomes of ticagrelor and clopidogrel stratified by estimated glomerular filtration rate (eGFR) in a large unselected cohort of patients with acute myocardial infarction (MI). Methods We used follow-up data in MI survivors discharged on ticagrelor or clopidogrel enrolled in the Swedish Web-System for Enhancement and Development of Evidence-Based Care in Heart Disease Evaluated According to Recommended Therapies registry. The association between ticagrelor versus clopidogrel and the primary composite outcome of death, MI or stroke and the secondary outcome rehospitalisation with bleeding diagnosis at 1year, was studied using adjusted Cox proportional hazards models, stratifying after eGFR levels. Results In total, 45 206 patients with MI discharged on clopidogrel (n=33472) or ticagrelor (n=11734) were included. The unadjusted 1-year event rate for the composite endpoint of death, MI or stroke was 7.0%, 18.0% and 48.0% for ticagrelor treatment and 11.0%, 33.0% and 64.0% for clopidogrel treatment in patients with eGFR(>60) (n=33668), eGFR(30-60) (n=9803) and eGFR(<30) (n=1735), respectively. After adjustment, ticagrelor as compared with clopidogrel was associated with a lower 1-year risk of the composite outcome (eGFR(>60): HR 0.87, 95%CI 0.76 to 99, eGFR(30-60): 0.82 (0.70 to 0.97), eGFR(<30): 0.95 (0.69 to 1.29), P for interaction=0.55) and a higher risk of bleeding (eGFR(>60): HR 1.10, 95%CI 0.90 to 1.35, eGFR(30-60): 1.13 (0.84 to 1.51), eGFR(<30): 1.79 (1.00 to 3.21), P for interaction=0.30) across the eGFR strata. Conclusions Treatment with ticagrelor as compared with clopidogrel in patients with MI was associated with lower risk for the composite of death, MI or stroke and a higher bleeding risk across all strata of eGFR. Of caution, bleeding events were more abundant in patients with eGFR(<30).
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| 28. |
- Fegraeus, Kim, et al.
(författare)
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An endothelial regulatory module links blood pressure regulation with elite athletic performance
- 2024
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Ingår i: PLOS Genetics. - : Public Library of Science (PLoS). - 1553-7390 .- 1553-7404. ; 20:6
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Tidskriftsartikel (refereegranskat)abstract
- The control of transcription is crucial for homeostasis in mammals. A previous selective sweep analysis of horse racing performance revealed a 19.6 kb candidate regulatory region 50 kb downstream of the Endothelin3 (EDN3) gene. Here, the region was narrowed to a 5.5 kb span of 14 SNVs, with elite and sub-elite haplotypes analyzed for association to racing performance, blood pressure and plasma levels of EDN3 in Coldblooded trotters and Standardbreds. Comparative analysis of human HiCap data identified the span as an enhancer cluster active in endothelial cells, interacting with genes relevant to blood pressure regulation. Coldblooded trotters with the sub-elite haplotype had significantly higher blood pressure compared to horses with the elite performing haplotype during exercise. Alleles within the elite haplotype were part of the standing variation in pre-domestication horses, and have risen in frequency during the era of breed development and selection. These results advance our understanding of the molecular genetics of athletic performance and vascular traits in both horses and humans.
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| 29. |
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| 30. |
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| 31. |
- Karjalainen, Suvi, et al.
(författare)
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A pilot study on the relationship between primary-school teachers’ well-being and the acoustics of their classrooms
- 2020
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Ingår i: International Journal of Environmental Research and Public Health. - : MDPI. - 1661-7827 .- 1660-4601. ; 17:6
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Tidskriftsartikel (refereegranskat)abstract
- Although teachers’ well-being and vocal health are affected by noise, research on classroom sound environment from the teachers’ perspective is scarce. This study investigated the relationship between teachers’ well-being and classroom acoustics. The possible influence of teachers’ age, experience, teaching grade and class size on the relationship was also investigated. In this study, well-being refers to self-reported vocal health, stress, burnout and self-efficacy. Twenty-three primary-school teachers answered questionnaires on well-being. In each teacher’s classroom, the acoustical properties were measured with the variables reverberation time, clarity of speech (C50) and ventilation system noise (VSN). A series of non-parametric correlations were run to determine the relationship between teachers’ well-being and classroom acoustics. Initially, there was a significant bivariate correlation between burnout and VSN, as well as voice symptoms correlated with VSN and teaching grade. Although the results became not significant after correction for multiple tests, the findings indicate that higher degree of burnout is associated with higher levels of VSN in classrooms, and voice symptoms increase with higher VSN. Teachers working in lower grades had more voice symptoms than those working in higher grades. © 2020 by the authors. Licensee MDPI, Basel, Switzerland.
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| 32. |
- Karjalainen, Suvi, et al.
(författare)
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Teachers' voice use and wellbeing in relation to the classroom acoustics and background noise
- 2023
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Ingår i: Proceedings of the 10<sup>th</sup> Convention of theEuropean Acoustics Association Forum Acusticum 2023. - : European Acoustics Association, EAA. - 9788888942674
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Konferensbidrag (refereegranskat)abstract
- Although many studies have shown that teachers' vocal health is challenged by noise and the room acoustics, research on classroom sound environment from the perspective of teachers' well-being is scarce. This study aimed to explore the relationship between teachers' wellbeing, voice use and classroom acoustics. In this study, wellbeing refers to self-reported vocal health, self-assessed level of stress, burnout and self-efficacy. Twenty-three primary-school teachers answered questionnaires on well-being. In each teacher's classroom, the acoustical properties were measured with the variables reverberation time, clarity of speech (C50) and ventilation system noise (VSN). A series of non-parametric correlations were run to determine the relationship between teachers' well-being and classroom acoustics. There was a significant bivariate correlation between burnout and VSN, (dBA), that, however, after correction for multiple analyses remained non significant, Voice symptoms correlated with VSN and teaching grade. This study indicates that higher degree of burnout in teachers is associated with higher levels of VSN in classrooms. Moreover, teachers' voice symptoms increase with higher levels of VSN. Teachers teaching lower grades had more voice symptoms than those teaching higher grades.
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| 33. |
- Kohli, Manpreet K, et al.
(författare)
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Extremely low genetic diversity in a circumpolar dragonfly species, Somatochlora sahlbergi (Insecta: Odonata: Anisoptera)
- 2018
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Ingår i: Scientific Reports. - London : Nature Publishing Group. - 2045-2322. ; 8, s. 1-10
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Tidskriftsartikel (refereegranskat)abstract
- We present the first empirical treatment of the northernmost breeding dragonfly, Somatochlora sahlbergi. We sequenced populations from United States, Canada, Finland, Sweden and Norway for cytochrome oxidase I (COI) and D2 region of 28s. We found that, despite geographic barriers across its vast arctic range, S. sahlbergi is a single species. Not only does it appear to interbreed across its entire range, there also seems to be almost no variation among European and North American populations in their COI gene fragment (the barcode gene), which is usually extremely variable. We further found that characters thought to be diagnostic for the larvae of S. sahlbergi were absent in our European samples. We review and re-describe the habitat of this species based on new findings from recent field observations. Finally, we report for the first time the likely presence of this species in Japan. We hope our findings will encourage further study of this species and other under-studied insect taxa that inhabit the remote Arctic.
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| 34. |
- Kohli, Sunil, 1955-, et al.
(författare)
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Distance from the primary health center : a GIS method to study geographical access to health care
- 1995
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Ingår i: Journal of medical systems. - 0148-5598 .- 1573-689X. ; 19:6, s. 425-436
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Tidskriftsartikel (refereegranskat)abstract
- Aerial distance from the dependent Primary Health Center is a crude but objective measure of geographical accessibility to Primary Health care facilities. This report describes a method for calculation of distances between the PHC and the population it serves using the data available from the local health authorities and the Swedish Central Statistical Bureau. The Swedish annual population registration records of 1991 and the property register available with the Central Statistical Bureau of Sweden formed the main data sources. By coupling the address in the population register to the property register each individual was mapped to the centroid of a property. The location of the PHCs as well as the areas covered by each were obtained from the local health authorities and mapped. By intersecting the population coverage with the PHC coverage the population for each PHC area was identified. Subsequently the distance to the PHC was calculated for each individual (property centroid). The population maps so generated can be linked to other databases to visualize and analyze the spatial dimension of health and disease. The methodology can be adapted for use with postal code districts, census enumeration tracts, or any other small area.
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| 35. |
- Kohli, Sunil, et al.
(författare)
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Individuals living in areas with high background radon : a GIS method to identify populations at risk
- 1997
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Ingår i: Computer Methods and Programs in Biomedicine. - 0169-2607 .- 1872-7565. ; 53:2, s. 105-112
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Tidskriftsartikel (refereegranskat)abstract
- Objective: to identify and link populations and individuals that live within high risk areas. Design: census registers and disease registers which contain data on individuals can only give aggregate statistics relating to postal code districts, town, county or state boundaries. However environmental risk factors rarely, if ever, respect these man-made boundaries. What is needed is a method to rapidly identify individuals who may live within a described area or region and to further identify the disease(s) occurring among these individuals and/or in these areas. Method: this paper describes a method for linking the standard registers available in Sweden, notably the residence-property addresses they contain and the geographical coordinate setting of these, to map the population as a point coverage. Using standard GIS methods this coverage could be linked, merged or intersected with any other map to create new subsets of population. Representation of populations down to the individual level by automatised spatialisation of available census data is in its simplicity a new informatics method which in the designated GIS medium adds a new power of resolution. Results: we demonstrate this using the radon maps provided by the local communes. The Swedish annual population registration records of 1991 for the county ofÖstergötland and the property register available at the Central Statistical Bureau of Sweden formed the main data sources. By coupling the address in the population register to the property register each individual was mapped to the centroid of a property. By intersecting the population coverage with the radon maps, the population living in high, normal or low risk areas was identified and then analysed and stratified by commune, sex and age. The resulting tables can be linked to other databases, e.g. disease registers, to visualise and analyse geographical and related patterns. The methodology can be adapted for use with any other environmental map or small area. It can also be expanded to the fourth dimension by linking likewise available migration information to generate immediately coordinate-set, accumulated exposition and similar data.
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| 36. |
- Kuijper, D. P. J., et al.
(författare)
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Paws without claws? Ecological effects of large carnivores in anthropogenic landscapes
- 2016
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Ingår i: Proceedings of the Royal Society of London. Biological Sciences. - : The Royal Society. - 0962-8452 .- 1471-2954. ; 283:1841
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Tidskriftsartikel (refereegranskat)abstract
- Large carnivores are frequently presented as saviours of biodiversity and ecosystem functioning through their creation of trophic cascades, an idea largely based on studies coming primarily out of relatively natural landscapes. However, in large parts of the world, particularly in Europe, large carnivores live in and are returning to strongly human-modified ecosystems. At present, we lack a coherent framework to predict the effects of large carnivores in these anthropogenic landscapes. We review how human actions influence the ecological roles of large carnivores by affecting their density or behaviour or those of mesopredators or prey species. We argue that the potential for density-mediated trophic cascades in anthropogenic landscapes is limited to unproductive areas where even low carnivore numbers may impact prey densities or to the limited parts of the landscape where carnivores are allowed to reach ecologically functional densities. The potential for behaviourally mediated trophic cascades may be larger and more widespread, because even low carnivore densities affect prey behaviour. We conclude that predator-prey interactions in anthropogenic landscapes will be highly context-dependent and human actions will often attenuate the ecological effects of large carnivores. We highlight the knowledge gaps and outline a new research avenue to study the role of carnivores in anthropogenic landscapes.
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| 37. |
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| 38. |
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| 39. |
- Pierre, M., et al.
(författare)
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The XXL survey : First results and future
- 2017
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Ingår i: Astronomical Notes - Astronomische Nachrichten. - : Wiley-VCH Verlagsgesellschaft. - 0004-6337 .- 1521-3994. ; 338:2-3, s. 334-341
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Tidskriftsartikel (refereegranskat)abstract
- The XXL survey currently covers two 25 deg(2) patches with XMM observations of similar to 10 ks. We summarize the scientific results associated with the first release of the XXL dataset, which occurred in mid-2016. We review several arguments for increasing the survey depth to 40 ks during the next decade of XMM operations. X-ray (z < 2) cluster, (z < 4) active galactic nuclei (AGN), and cosmic background survey science will then benefit from an extraordinary data reservoir. This, combined with deep multi-lambda observations, will lead to solid standalone cosmological constraints and provide a wealth of information on the formation and evolution of AGN, clusters, and the X-ray background. In particular, it will offer a unique opportunity to pinpoint the z > 1 cluster density. It will eventually constitute a reference study and an ideal calibration field for the upcoming eROSITA and Euclid missions.
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| 40. |
- Rudner, Mary, 1958-, et al.
(författare)
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Listening comprehension and listening effort in the primary school classroom
- 2018
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Ingår i: Frontiers in Psychology. - : Frontiers Media SA. - 1664-1078. ; 9:JUN
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Tidskriftsartikel (refereegranskat)abstract
- In the primary school classroom, children are exposed to multiple factors that combine to create adverse conditions for listening to and understanding what the teacher is saying. Despite the ubiquity of these conditions, there is little knowledge concerning the way in which various factors combine to influence listening comprehension and the effortfulness of listening. The aim of the present study was to investigate the combined effects of background noise, voice quality, and visual cues on children's listening comprehension and effort. To achieve this aim, we performed a set of four well-controlled, yet ecologically valid, experiments with 245 eight-year-old participants. Classroom listening conditions were simulated using a digitally animated talker with a dysphonic (hoarse) voice and background babble noise composed of several children talking. Results show that even low levels of babble noise interfere with listening comprehension, and there was some evidence that this effect was reduced by seeing the talker's face. Dysphonia did not significantly reduce listening comprehension scores, but it was considered unpleasant and made listening seem difficult, probably by reducing motivation to listen. We found some evidence that listening comprehension performance under adverse conditions is positively associated with individual differences in executive function. Overall, these results suggest that multiple factors combine to influence listening comprehension and effort for child listeners in the primary school classroom. The constellation of these room, talker, modality, and listener factors should be taken into account in the planning and design of educational and learning activities.
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| 41. |
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| 42. |
- Sahlen, Anders, et al.
(författare)
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Contemporary use of ticagrelor in patients with acute coronary syndrome : insights from Swedish Web System for Enhancement and Development of Evidence-Based Care in Heart Disease Evaluated According to Recommended Therapies (SWEDEHEART)
- 2016
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Ingår i: EUROPEAN HEART JOURNAL-CARDIOVASCULAR PHARMACOTHERAPY. - : Oxford University Press (OUP). - 2055-6837 .- 2055-6845. ; 2:1, s. 5-12
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Tidskriftsartikel (refereegranskat)abstract
- The platelet inhibitor ticagrelor is strongly recommended during 12 months post-acute coronary syndrome (ACS) in European guidelines. We analysed clinical characteristics of patients given ticagrelor for ACS in the real world. We studied the use of ticagrelor in patients admitted for ACS in Sweden between 1 January 2012 and 31 December 2013 who were enrolled in the Swedish Web system for Enhancement and Development of Evidence-based care in Heart disease Evaluated According to Recommended Therapies (SWEDEHEART). Clinical characteristics were investigated for patients prescribed ticagrelor at discharge as well as for patients undergoing percutaneous coronary intervention who were prescribed ticagrelor. Independent factors associated with selecting ticagrelor were analysed in logistic regression. We found that 44.0% (n = 12 601) out of a total of 28 639 patients had been prescribed ticagrelor at discharge. After adjusting for age and sex, prior cardiovascular disease was less common in patients discharged on ticagrelor (myocardial infarction, ischaemic stroke, and peripheral vascular disease; P for all < 0.001). The risk of death as predicted by GRACE score and the risk of major bleeding as predicted by CRUSADE score were both lower in ticagrelor-treated patients vs. others (median 99 vs. 126 and median 23 vs. 25, respectively; P for both < 0.001). The intended treatment duration at discharge was 12 months in 82.5% of patients and < 12 months in 9.3%. Ticagrelor is preferentially being used in patients at lower risk. A minority of patients are recommended ticagrelor during < 12 months.
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| 43. |
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| 44. |
- Sahlen, A., et al.
(författare)
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Outcomes in patients treated with ticagrelor or clopidogrel after acute myocardial infarction: experiences from SWEDEHEART registry
- 2016
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Ingår i: European Heart Journal. - : Oxford University Press (OUP). - 0195-668X .- 1522-9645. ; 37:44, s. 3335-3342
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Tidskriftsartikel (refereegranskat)abstract
- Aims Ticagrelor reduces ischaemic events and mortality in acute coronary syndrome (ACS) vs. clopidogrel. We wished to study clinical outcomes in a large real-world population post-ACS. Methods and results We performed a prospective cohort study in 45 073 ACS patients enrolled into SwedishWeb system for Enhancement and Development of Evidence-based care in Heart Disease Evaluated According to Recommended Therapies who were discharged on ticagrelor (N = 11 954) or clopidogrel (N = 33 119) between 1 January 2010 and 31 December 2013. The primary outcome was a composite of all-cause death, re-admission with myocardial infarction (MI) or stroke, secondary outcomes as the individual components of the primary outcome, and re-admission with bleeding. The risk of the primary outcome with ticagrelor vs. clopidogrel was 11.7 vs. 22.3% (adjusted hazard ratio (HR) 0.85 [95% confidence interval: 0.78-0.93]), risk of death 5.8 vs. 12.9% (adjusted HR 0.83 [0.75-0.92]), and risk of MI 6.1 vs. 10.8% (adjusted HR 0.89 [0.78-1.01]) at 24 months. Re-admission with bleeding with ticagrelor vs. clopidogrel occurred in 5.5 vs. 5.2% (adjusted HR 1.20 [1.04-1.40]). In a subset of patients undergoing percutaneous coronary intervention (PCI) on ticagrelor vs. clopidogrel the PCI-related in-hospital bleeding was 3.7 vs. 2.7% (adjusted odds ratio, OR, 1.57 [1.30-1.90]). Conclusion Ticagrelor vs. clopidogrel post-ACS was associated with a lower risk of death, MI, or stroke, as well as death alone. Risk of bleeding was higher with ticagrelor. These real-world outcomes are consistent with randomized trial results.
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| 45. |
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| 46. |
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| 47. |
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| 48. |
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| 49. |
- Stott, J. P., et al.
(författare)
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THE XMM CLUSTER SURVEY : THE BUILD-UP OF STELLAR MASS IN BRIGHTEST CLUSTER GALAXIES AT HIGH REDSHIFT
- 2010
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Ingår i: Astrophysical Journal. - 0004-637X .- 1538-4357. ; 718:1, s. 23-30
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Tidskriftsartikel (refereegranskat)abstract
- We present deep J-and K-s-band photometry of 20 high redshift galaxy clusters between z = 0.8 and 1.5, 19 of which are observed with the MOIRCS instrument on the Subaru telescope. By using near-infrared light as a proxy for stellar mass we find the surprising result that the average stellar mass of Brightest Cluster Galaxies (BCGs) has remained constant at similar to 9 x 10(11) M-circle dot since z similar to 1.5. We investigate the effect on this result of differing star formation histories generated by three well-known and independent stellar population codes and find it to be robust for reasonable, physically motivated choices of age and metallicity. By performing Monte Carlo simulations we find that the result is unaffected by any correlation between BCG mass and cluster mass in either the observed or model clusters. The large stellar masses imply that the assemblage of these galaxies took place at the same time as the initial burst of star formation. This result leads us to conclude that dry merging has had little effect on the average stellar mass of BCGs over the last 9-10 Gyr in stark contrast to the predictions of semi-analytic models, based on the hierarchical merging of dark matter halos, which predict a more protracted mass build-up over a Hubble time. However, we discuss that there is potential for reconciliation between observation and theory if there is a significant growth of material in the intracluster light over the same period.
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| 50. |
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