| 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. |
- 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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| 4. |
- 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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| 5. |
- 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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| 6. |
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| 7. |
- 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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| 8. |
- 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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| 9. |
- 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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| 10. |
- 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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| 11. |
- 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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| 12. |
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| 13. |
- 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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| 14. |
- 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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| 15. |
- 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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| 16. |
- 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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| 17. |
- 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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| 18. |
- 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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| 19. |
- Venkateshvaran, Ashwin, et al.
(författare)
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The impact of arterial load on left ventricular performance : An invasive haemodynamic study in severe mitral stenosis
- 2015
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Ingår i: Journal of Physiology. - : Wiley. - 0022-3751 .- 1469-7793. ; 593:8, s. 1901-1912
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Tidskriftsartikel (refereegranskat)abstract
- Key points: A hallmark of mitral stenosis (MS) is the markedly altered left ventricular (LV) loading. As most of the methods used to determine LV performance in MS patients are influenced by loading conditions, previous studies have shown conflicting results. The present study calculated LV elastance, which is a robust method to quantify LV function. We demonstrate that LV loading in MS patients is elevated but normalizes after valve repair and might be a result of reflex pathways. Additionally, we show that the LV in MS is less compliant than normal due to a combination of right ventricular loading and the valvular disease itself. Immediately after valve dilatation the increase in blood inflow into the LV results in even greater LV stiffness. Our findings enrich our understanding of heart function in MS patients and provide a simple reproducible way of assessing LV performance in MS. Left ventricular (LV) function in rheumatic mitral stenosis (MS) remains an issue of controversy, due to load dependency of previously employed assessment methods. We investigated LV performance in MS employing relatively load-independent indices robust to the altered loading state. We studied 106 subjects (32 ± 8 years, 72% female) with severe MS (0.8 ± 0.2 cm2) and 40 age-matched controls. MS subjects underwent simultaneous bi-ventricular catheterization and transthoracic echocardiography (TTE) before and immediately after percutaneous transvenous mitral commisurotomy (PTMC). Sphygmomanometric brachial artery pressures and TTE recordings were simultaneously acquired in controls. Single-beat LV elastance (Ees) was employed for LV contractility measurements. Effective arterial elastance (Ea) and LV diastolic stiffness were measured. MS patients demonstrated significantly elevated afterload (Ea: 3.0 ± 1.3 vs. 1.5 ± 0.3 mmHg ml-1; P < 0.001) and LV contractility (Ees: 4.1 ± 1.6 vs. 2.4 ± 0.5 mmHg ml-1; P < 0.001) as compared to controls, with higher Ea in subjects with smaller mitral valve area (≤ 0.8 cm2) and pronounced subvalvular fusion. Stroke volume (49 ± 16 to 57 ± 17 ml; P < 0.001) and indexed LV end-diastolic volume (LVEDVindex: 57 ± 16 to 64 ± 16 ml m-2; P < 0.001) increased following PTMC while Ees and Ea returned to more normal levels. Elevated LV stiffness was demonstrated at baseline and increased further following PTMC. Our findings provide evidence of elevated LV contractility, increased arterial load and increased diastolic stiffness in severe MS. Following PTMC, both LV contractility and afterload tend to normalize.
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| 20. |
- von Lochow, Heike, et al.
(författare)
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The effect of voice quality and competing speakers in a passage comprehension task : perceived effort in relation to cognitive functioning and performance in children with normal hearing
- 2018
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Ingår i: Logopedics Phoniatrics Vocology. - : Informa UK Limited. - 1401-5439 .- 1651-2022. ; 43:1, s. 32-41
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Tidskriftsartikel (refereegranskat)abstract
- The study investigates the effect of voice quality and competing speakers on perceived effort in a passage comprehension task in relation to cognitive functioning. In addition, it explores if perceived effort was related to performance. A total of 49 children (aged 7:03 to 12:02 years) with normal hearing participated. The children performed an auditory passage comprehension task presented with six different listening conditions consisting of a typical voice or a dysphonic voice presented in quiet, with one competing speaker, and with four competing speakers. After completing the task, they rated their perceived effort on a five-grade scale. The children also performed tasks measuring working memory capacity (WMC) and executive functioning. The results show that voice quality had no direct effect on perceived effort but the children’s ratings of perceived effort were related to their executive functioning. A significant effect was seen for background listening condition indicating higher perceived effort for background listening conditions with competing speakers. The effects of background listening condition were mainly related to the children’s WMC but also their executive functioning. It can be concluded that the individual susceptibility to the effect of the dysphonic voice is related to the child’s executive functioning. The individual susceptibility to the presence of competing speakers is related to the child’s WMC and executive functioning.
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| 21. |
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