| 1. |
- Prusti, T., et al.
(författare)
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The Gaia mission
- 2016
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Ingår i: Astronomy and Astrophysics. - : EDP Sciences. - 0004-6361 .- 1432-0746. ; 595
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Tidskriftsartikel (refereegranskat)abstract
- Gaia is a cornerstone mission in the science programme of the European Space Agency (ESA). The spacecraft construction was approved in 2006, following a study in which the original interferometric concept was changed to a direct-imaging approach. Both the spacecraft and the payload were built by European industry. The involvement of the scientific community focusses on data processing for which the international Gaia Data Processing and Analysis Consortium (DPAC) was selected in 2007. Gaia was launched on 19 December 2013 and arrived at its operating point, the second Lagrange point of the Sun-Earth-Moon system, a few weeks later. The commissioning of the spacecraft and payload was completed on 19 July 2014. The nominal five-year mission started with four weeks of special, ecliptic-pole scanning and subsequently transferred into full-sky scanning mode. We recall the scientific goals of Gaia and give a description of the as-built spacecraft that is currently (mid-2016) being operated to achieve these goals. We pay special attention to the payload module, the performance of which is closely related to the scientific performance of the mission. We provide a summary of the commissioning activities and findings, followed by a description of the routine operational mode. We summarise scientific performance estimates on the basis of in-orbit operations. Several intermediate Gaia data releases are planned and the data can be retrieved from the Gaia Archive, which is available through the Gaia home page.
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| 2. |
- Brown, A. G. A., et al.
(författare)
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Gaia Data Release 1 Summary of the astrometric, photometric, and survey properties
- 2016
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Ingår i: Astronomy and Astrophysics. - : EDP Sciences. - 0004-6361 .- 1432-0746. ; 595
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Tidskriftsartikel (refereegranskat)abstract
- Context. At about 1000 days after the launch of Gaia we present the first Gaia data release, Gaia DR1, consisting of astrometry and photometry for over 1 billion sources brighter than magnitude 20.7. Aims. A summary of Gaia DR1 is presented along with illustrations of the scientific quality of the data, followed by a discussion of the limitations due to the preliminary nature of this release. Methods. The raw data collected by Gaia during the first 14 months of the mission have been processed by the Gaia Data Processing and Analysis Consortium (DPAC) and turned into an astrometric and photometric catalogue. Results. Gaia DR1 consists of three components: a primary astrometric data set which contains the positions, parallaxes, and mean proper motions for about 2 million of the brightest stars in common with the HIPPARCOS and Tycho-2 catalogues - a realisation of the Tycho-Gaia Astrometric Solution (TGAS) - and a secondary astrometric data set containing the positions for an additional 1.1 billion sources. The second component is the photometric data set, consisting of mean G-band magnitudes for all sources. The G-band light curves and the characteristics of similar to 3000 Cepheid and RR Lyrae stars, observed at high cadence around the south ecliptic pole, form the third component. For the primary astrometric data set the typical uncertainty is about 0.3 mas for the positions and parallaxes, and about 1 mas yr(-1) for the proper motions. A systematic component of similar to 0.3 mas should be added to the parallax uncertainties. For the subset of similar to 94 000 HIPPARCOS stars in the primary data set, the proper motions are much more precise at about 0.06 mas yr(-1). For the secondary astrometric data set, the typical uncertainty of the positions is similar to 10 mas. The median uncertainties on the mean G-band magnitudes range from the mmag level to similar to 0.03 mag over the magnitude range 5 to 20.7. Conclusions. Gaia DR1 is an important milestone ahead of the next Gaia data release, which will feature five-parameter astrometry for all sources. Extensive validation shows that Gaia DR1 represents a major advance in the mapping of the heavens and the availability of basic stellar data that underpin observational astrophysics. Nevertheless, the very preliminary nature of this first Gaia data release does lead to a number of important limitations to the data quality which should be carefully considered before drawing conclusions from the data.
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| 3. |
- Clementini, G., et al.
(författare)
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Testing parallaxes with local Cepheids and RR Lyrae stars
- 2017
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Ingår i: Astronomy and Astrophysics. - : EDP Sciences. - 0004-6361 .- 1432-0746. ; 605
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Tidskriftsartikel (refereegranskat)abstract
- Context. Parallaxes for 331 classical Cepheids, 31 Type II Cepheids, and 364 RR Lyrae stars in common between Gaia and the HIPPARCOS and Tycho-2 catalogues are published in Gaia Data Release 1 (DR1) as part of the Tycho-Gaia Astrometric Solution (TGAS). Aims. In order to test these first parallax measurements of the primary standard candles of the cosmological distance ladder, which involve astrometry collected by Gaia during the initial 14 months of science operation, we compared them with literature estimates and derived new period-luminosity (PL), period-Wesenheit (PW) relations for classical and Type II Cepheids and infrared PL, PL-metallicity (PLZ), and optical luminosity-metallicity (MV-[Fe/H]) relations for the RR Lyrae stars, with zero points based on TGAS.Methods. Classical Cepheids were carefully selected in order to discard known or suspected binary systems. The final sample comprises 102 fundamental mode pulsators with periods ranging from 1.68 to 51.66 days (of which 33 with sigma(omega)/omega < 0 : 5). The Type II Cepheids include a total of 26 W Virginis and BL Herculis stars spanning the period range from 1.16 to 30.00 days (of which only 7 with sigma(omega)/omega 0 : 5). The RR Lyrae stars include 200 sources with pulsation period ranging from 0.27 to 0.80 days (of which 112 with sigma(omega)/omega < 0 : 5). The new relations were computed using multi- band (V; I; J; K-s) photometry and spectroscopic metal abundances available in the literature, and by applying three alternative approaches: (i) linear least-squares fitting of the absolute magnitudes inferred from direct transformation of the TGAS parallaxes; (ii) adopting astrometry-based luminosities; and (iii) using a Bayesian fitting approach. The last two methods work in parallax space where parallaxes are used directly, thus maintaining symmetrical errors and allowing negative parallaxes to be used. The TGAS-based PL; PW; PLZ, and MV [Fe/H] relations are discussed by comparing the distance to the Large Magellanic Cloud provided by different types of pulsating stars and alternative fitting methods.Results. Good agreement is found from direct comparison of the parallaxes of RR Lyrae stars for which both TGAS and HST measurements are available. Similarly, very good agreement is found between the TGAS values and the parallaxes inferred from the absolute magnitudes of Cepheids and RR Lyrae stars analysed with the Baade-Wesselink method. TGAS values also compare favourably with the parallaxes inferred by theoretical model fitting of the multi-band light curves for two of the three classical Cepheids and one RR Lyrae star, which were analysed with this technique in our samples. The K-band PL relations show the significant improvement of the TGAS parallaxes for Cepheids and RR Lyrae stars with respect to the HIPPARCOS measurements. This is particularly true for the RR Lyrae stars for which improvement in quality and statistics is impressive.Conclusions. TGAS parallaxes bring a significant added value to the previous HIPPARCOS estimates. The relations presented in this paper represent the first Gaia-calibrated relations and form a work-in-progress milestone report in the wait for Gaia-only parallaxes of which a first solution will become available with Gaia Data Release 2 (DR2) in 2018.
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| 4. |
- van Leeuwen, F., et al.
(författare)
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Gaia Data Release 1 : Open cluster astrometry: Performance, limitations, and future prospects
- 2017
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Ingår i: Astronomy and Astrophysics. - : EDP Sciences. - 0004-6361 .- 1432-0746. ; 601
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Tidskriftsartikel (refereegranskat)abstract
- Context. The first Gaia Data Release contains the Tycho-Gaia Astrometric Solution (TGAS). This is a subset of about 2 million stars for which, besides the position and photometry, the proper motion and parallax are calculated using Hipparcos and Tycho-2 positions in 1991.25 as prior information. Aims. We investigate the scientific potential and limitations of the TGAS component by means of the astrometric data for open clusters. Methods. Mean cluster parallax and proper motion values are derived taking into account the error correlations within the astrometric solutions for individual stars, an estimate of the internal velocity dispersion in the cluster, and, where relevant, the effects of the depth of the cluster along the line of sight. Internal consistency of the TGAS data is assessed. Results. Values given for standard uncertainties are still inaccurate and may lead to unrealistic unit-weight standard deviations of least squares solutions for cluster parameters. Reconstructed mean cluster parallax and proper motion values are generally in very good agreement with earlier Hipparcos-based determination, although the Gaia mean parallax for the Pleiades is a significant exception. We have no current explanation for that discrepancy. Most clusters are observed to extend to nearly 15 pc from the cluster centre, and it will be up to future Gaia releases to establish whether those potential cluster-member stars are still dynamically bound to the clusters. Conclusions. The Gaia DR1 provides the means to examine open clusters far beyond their more easily visible cores, and can provide membership assessments based on proper motions and parallaxes. A combined HR diagram shows the same features as observed before using the Hipparcos data, with clearly increased luminosities for older A and F dwarfs.
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| 5. |
- Sumaila, U. Rashid, et al.
(författare)
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WTO must ban harmful fisheries subsidies
- 2021
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Ingår i: Science. - : American Association for the Advancement of Science (AAAS). - 0036-8075 .- 1095-9203. ; 374:6567, s. 544-544
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Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)
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| 6. |
- Lacour, S., et al.
(författare)
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The mass of β Pictoris c from β Pictoris b orbital motion
- 2021
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Ingår i: Astronomy and Astrophysics. - : EDP Sciences. - 0004-6361 .- 1432-0746. ; 654
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Tidskriftsartikel (refereegranskat)abstract
- Aims. We aim to demonstrate that the presence and mass of an exoplanet can now be effectively derived from the astrometry of another exoplanet.Methods. We combined previous astrometry of β Pictoris b with a new set of observations from the GRAVITY interferometer. The orbital motion of β Pictoris b is fit using Markov chain Monte Carlo simulations in Jacobi coordinates. The inner planet, β Pictoris c, was also reobserved at a separation of 96 mas, confirming the previous orbital estimations.Results. From the astrometry of planet b only, we can (i) detect the presence of β Pictoris c and (ii) constrain its mass to 10.04(-3.10)(+4.53) M-Jup. If one adds the astrometry of β Pictoris c, the mass is narrowed down to 9.15(-1.06)(+1.08) M-Jup. The inclusion of radial velocity measurements does not affect the orbital parameters significantly, but it does slightly decrease the mass estimate to 8.89(-0.75)(+0.75) M-Jup. With a semimajor axis of 2.68 +/- 0.02 au, a period of 1221 +/- 15 days, and an eccentricity of 0.32 +/- 0.02, the orbital parameters of β Pictoris c are now constrained as precisely as those of β Pictoris b. The orbital configuration is compatible with a high-order mean-motion resonance (7:1). The impact of the resonance on the planets' dynamics would then be negligible with respect to the secular perturbations, which might have played an important role in the eccentricity excitation of the outer planet.
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| 7. |
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| 8. |
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| 9. |
- Ip, H. F., et al.
(författare)
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Genetic association study of childhood aggression across raters, instruments, and age
- 2021
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Ingår i: Translational Psychiatry. - : Springer Science and Business Media LLC. - 2158-3188. ; 11:1
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Tidskriftsartikel (refereegranskat)abstract
- Childhood aggressive behavior (AGG) has a substantial heritability of around 50%. Here we present a genome-wide association metaanalysis (GWAMA) of childhood AGG, in which all phenotype measures across childhood ages from multiple assessors were included. We analyzed phenotype assessments for a total of 328 935 observations from 87 485 children aged between 1.5 and 18 years, while accounting for sample overlap. We also meta-analyzed within subsets of the data, i.e., within rater, instrument and age. SNP-heritability for the overall meta-analysis (AGGoverall) was 3.31% (SE= 0.0038). We found no genome-wide significant SNPs for AGG(overall). The gene-based analysis returned three significant genes: ST3GAL3 (P= 1.6E-06), PCDH7 (P= 2.0E-06), and IPO13 (P= 2.5E-06). All three genes have previously been associated with educational traits. Polygenic scores based on our GWAMA significantly predicted aggression in a holdout sample of children (variance explained = 0.44%) and in retrospectively assessed childhood aggression (variance explained = 0.20%). Genetic correlations (rg) among rater-specific assessment of AGG ranged from r(g)= 0.46 between self- and teacher-assessment to r(g)d= 0.81 between mother- and teacher-assessment. We obtained moderate-to-strong rgs with selected phenotypes from multiple domains, but hardly with any of the classical biomarkers thought to be associated with AGG. Significant genetic correlations were observed with most psychiatric and psychological traits (range r(g): 0.19-1.00), except for obsessive-compulsive disorder. Aggression had a negative genetic correlation (r(g)=-0.5) with cognitive traits and age at first birth. Aggression was strongly genetically correlated with smoking phenotypes (range |r(g)| : 0.46-0.60). The genetic correlations between aggression and psychiatric disorders were weaker for teacher-reported AGG than for mother- and self-reported AGG. The current GWAMA of childhood aggression provides a powerful tool to interrogate the rater-specific genetic etiology of AGG.
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| 10. |
- Hillege, H. L., et al.
(författare)
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Renal function as a predictor of outcome in a broad spectrum of patients with heart failure
- 2006
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Ingår i: Circulation. - 1524-4539 .- 0009-7322. ; 113:5, s. 671-8
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: Decreased renal function has been found to be an independent risk factor for cardiovascular outcomes in patients with chronic heart failure (CHF) with markedly reduced left ventricular ejection fraction (LVEF). The aim of this analysis was to evaluate the prognostic importance of renal function in a broader spectrum of patients with CHF. METHODS AND RESULTS: The Candesartan in Heart Failure:Assessment of Reduction in Mortality and Morbidity (CHARM) program consisted of three component trials that enrolled patients with symptomatic CHF, based on use of ACE inhibitors and reduced (< or =40%) or preserved LVEF (>40%). Entry baseline creatinine was required to be below 3.0 mg/dL (265 micromol/L). Routine baseline serum creatinine assessments were done in 2680 North American patients. An analysis of the estimated glomerular filtration rate (eGFR), using the Modification of Diet in Renal Disease equation and LVEF on risk of cardiovascular death or hospitalization for heart failure, as well as on all-cause mortality, was conducted on these 2680 patients. The proportion of patients with eGFR <60 mL/min per 1.73 m2 was 36.0%; 42.6% for CHARM-Alternative, 33.0% for CHARM-Added, and 34.7% for CHARM-Preserved. During the median follow-up of 34.4 months (total 6493 person-years), the primary outcome of cardiovascular death or hospital admission for worsening CHF occurred in 950 of 2680 subjects. Both reduced eGFR and lower LVEF were found to be significant independent predictors of worse outcome after adjustment for major confounding baseline clinical characteristics. The risk for cardiovascular death or hospitalization for worsening CHF as well as the risk for all-cause mortality increased significantly below an eGFR of 60 mL/min per 1.73 m2 (adjusted hazard ratio, 1.54 for 45 to 60 mL/min per 1.73 m2 and 1.86 for <45 mL/min per 1.73 m2 for the primary outcome, both P<0.001, and hazard ratio of 1.50, P=0.006, and 1.91, P=0.001, respectively, for all-cause mortality). The prognostic value of eGFR was not significantly different among the three component trials. There was no significant interaction between renal function, the effect of candesartan, and clinical outcome. CONCLUSIONS: Impaired renal function is independently associated with heightened risk for death, cardiovascular death, and hospitalization for heart failure in patients with CHF with both preserved as well as reduced LVEF. There was no evidence that the beneficial effect of candesartan was modified by baseline eGFR.
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| 11. |
- Lundgren, A., et al.
(författare)
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APEX: Five years of operations
- 2010
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Ingår i: Proceedings of SPIE - The International Society for Optical Engineering. - : SPIE. - 0277-786X .- 1996-756X. - 9780819482273 ; 7737
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Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- APEX, the Atacama Pathfinder EXperiment, is being operated successfully, now for five years, on Llano de Chajnantor at 5107m altitude in the Chilean High Andes. This location is considered one of the worlds outstanding sites for submillimeter astronomy, which the results described in this contribution are underlining. The primary reflector with 12 m diameter is cautiously being maintained at about 15 μm by means of holography. This allows to access all atmospheric submillimeter windows accessible from the ground, up to 200 μm. Telescope and instrument performance, operational experiences and a selection of scientific results are given in this publication. © 2010 Copyright SPIE - The International Society for Optical Engineering.
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| 12. |
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| 13. |
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| 14. |
- Price, KM, et al.
(författare)
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Hypothesis-driven genome-wide association studies provide novel insights into genetics of reading disabilities
- 2022
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Ingår i: Translational psychiatry. - : Springer Science and Business Media LLC. - 2158-3188. ; 12:1, s. 495-
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Tidskriftsartikel (refereegranskat)abstract
- Reading Disability (RD) is often characterized by difficulties in the phonology of the language. While the molecular mechanisms underlying it are largely undetermined, loci are being revealed by genome-wide association studies (GWAS). In a previous GWAS for word reading (Price, 2020), we observed that top single-nucleotide polymorphisms (SNPs) were located near to or in genes involved in neuronal migration/axon guidance (NM/AG) or loci implicated in autism spectrum disorder (ASD). A prominent theory of RD etiology posits that it involves disturbed neuronal migration, while potential links between RD-ASD have not been extensively investigated. To improve power to identify associated loci, we up-weighted variants involved in NM/AG or ASD, separately, and performed a new Hypothesis-Driven (HD)–GWAS. The approach was applied to a Toronto RD sample and a meta-analysis of the GenLang Consortium. For the Toronto sample (n = 624), no SNPs reached significance; however, by gene-set analysis, the joint contribution of ASD-related genes passed the threshold (p~1.45 × 10–2, threshold = 2.5 × 10–2). For the GenLang Cohort (n = 26,558), SNPs in DOCK7 and CDH4 showed significant association for the NM/AG hypothesis (sFDR q = 1.02 × 10–2). To make the GenLang dataset more similar to Toronto, we repeated the analysis restricting to samples selected for reading/language deficits (n = 4152). In this GenLang selected subset, we found significant association for a locus intergenic between BTG3-C21orf91 for both hypotheses (sFDR q < 9.00 × 10–4). This study contributes candidate loci to the genetics of word reading. Data also suggest that, although different variants may be involved, alleles implicated in ASD risk may be found in the same genes as those implicated in word reading. This finding is limited to the Toronto sample suggesting that ascertainment influences genetic associations.
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| 15. |
- Rådholm, Karin, 1976-, et al.
(författare)
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Canagliflozin and Heart Failure in Type 2 Diabetes Mellitus: Results From the CANVAS Program
- 2018
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Ingår i: Circulation. - : LIPPINCOTT WILLIAMS & WILKINS. - 0009-7322 .- 1524-4539. ; 138:5, s. 458-468
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Tidskriftsartikel (refereegranskat)abstract
- Background: Canagliflozin is a sodium glucose cotransporter 2 inhibitor that reduces the risk of cardiovascular events. We report the effects on heart failure (HF) and cardiovascular death overall, in those with and without a baseline history of HF, and in other participant subgroups. Methods: The CANVAS Program (Canagliflozin Cardiovascular Assessment Study) enrolled 10142 participants with type 2 diabetes mellitus and high cardiovascular risk. Participants were randomly assigned to canagliflozin or placebo and followed for a mean of 188 weeks. The primary end point for these analyses was adjudicated cardiovascular death or hospitalized HF. Results: Participants with a history of HF at baseline (14.4%) were more frequently women, white, and hypertensive and had a history of prior cardiovascular disease (all Pamp;lt;0.001). Greater proportions of these patients were using therapies such as blockers of the renin angiotensin aldosterone system, diuretics, and -blockers at baseline (all Pamp;lt;0.001). Overall, cardiovascular death or hospitalized HF was reduced in those treated with canagliflozin compared with placebo (16.3 versus 20.8 per 1000 patient-years; hazard ratio [HR], 0.78; 95% confidence interval [CI], 0.67-0.91), as was fatal or hospitalized HF (HR, 0.70; 95% CI, 0.55-0.89) and hospitalized HF alone (HR, 0.67; 95% CI, 0.52-0.87). The benefit on cardiovascular death or hospitalized HF may be greater in patients with a prior history of HF (HR, 0.61; 95% CI, 0.46-0.80) compared with those without HF at baseline (HR, 0.87; 95% CI, 0.72-1.06; P interaction =0.021). The effects of canagliflozin compared with placebo on other cardiovascular outcomes and key safety outcomes were similar in participants with and without HF at baseline (all interaction P values amp;gt;0.130), except for a possibly reduced absolute rate of events attributable to osmotic diuresis among those with a prior history of HF (P=0.03). Conclusions: In patients with type 2 diabetes mellitus and an elevated risk of cardiovascular disease, canagliflozin reduced the risk of cardiovascular death or hospitalized HF across a broad range of different patient subgroups. Benefits may be greater in those with a history of HF at baseline. Clinical Trial Registration: URL: https://www.clinicaltrials.gov. Unique identifiers: NCT01032629 and NCT01989754.
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| 16. |
- Smaragdos, G., et al.
(författare)
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Performance Analysis of Accelerated Biophysically-Meaningful Neuron Simulations
- 2016
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Ingår i: 2016 Ieee International Symposium on Performance Analysis of Systems and Software Ispass 2016. - 9781509019533 ; , s. 1-11
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Konferensbidrag (refereegranskat)abstract
- In-vivo and in-vitro experiments are routinely used in neuroscience to unravel brain functionality. Although they are a powerful experimentation tool, they are also time-consuming and, often, restrictive. Computational neuroscience attempts to solve this by using biologically-plausible and biophysically-meaningful neuron models, most prominent among which are the conductance-based models. Their computational complexity calls for accelerator-based computing to mount large-scale or real-time neuroscientific experiments. In this paper, we analyze and draw conclusions on the class of conductance models by using a representative modeling application of the inferior olive (InfOli), an important part of the olivocerebellar brain circuit. We conduct an extensive profiling session to identify the computational and data-transfer requirements of the application under various realistic use cases. The application is, then, ported onto two acceleration nodes, an Intel Xeon Phi and a Maxeler Vectis Data Flow Engine (DFE). We evaluate the performance scalability and resource requirements of the InfOli application on the two target platforms. The analysis of InfOli, which is a real-life neuroscientific application, can serve as a useful guide for porting a wide range of similar workloads on platforms like the Xeon Phi or the Maxeler DFEs. As accelerators are increasingly populating High-Performance Computing (HPC) infrastructure, the current paper provides useful insight on how to optimally use such nodes to run complex and relevant neuron modeling workloads.
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| 17. |
- Smink, P. A., et al.
(författare)
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A prediction of the renal and cardiovascular efficacy of aliskiren in ALTITUDE using short-term changes in multiple risk markers
- 2014
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Ingår i: European Journal of Preventive Cardiology. - : Oxford University Press (OUP). - 2047-4873 .- 2047-4881. ; 21:4, s. 434-441
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Tidskriftsartikel (refereegranskat)abstract
- Introduction We recently developed and validated in existing trials a novel algorithm (PRE score) to predict long-term drug efficacy based on short-term (month-6) drug-induced changes in multiple risk markers. To show the value of the PRE score for ongoing and planned clinical trials, we here report the predicted long-term cardio-renal efficacy of aliskiren in type 2 diabetes, which was investigated in the ALTITUDE trial, but unknown at the time this study was conducted. Methods We established the relation between multiple risk markers and cardio-renal endpoints (as defined in ALTITUDE) using a background database from past clinical trials. The short-term effect of aliskiren on multiple risk markers was taken from the AVOID trial. A PRE score was developed by multivariate Cox analysis in the background population and was then applied to the baseline and month-6 measurements of the aliskiren treatment arm of the AVOID trial to predict cardio-renal risk. The net risk difference at these time-points, after correction for placebo effects, was taken to indicate the estimated long-term cardio-renal risk change. Results Based on the PRE score, we predicted that aliskiren treatment in ALTITUDE would confer a relative risk change of -7.9% (95% CI -2.5 to -13.4) for the cardio-renal endpoint, a risk change of -5.1% (-1.2 to -9.0) for the CV endpoint and a non-significant risk change of -19.9% (-42.1 to +2.1) for the renal endpoint. Conclusions PRE score estimations suggested that aliskiren has only a marginal additive protective effect on cardio-renal endpoints. These predictions were validated by the results of the ALTITUDE trial, confirming the potential of the PRE score to prospectively predict drug efficacy on cardio-renal outcomes.
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| 18. |
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| 19. |
- Eijkelkamp, W. B., et al.
(författare)
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Renal function and risk for cardiovascular events in type 2 diabetic patients with hypertension: the RENAAL and LIFE studies
- 2007
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Ingår i: J Hypertens. - 0263-6352. ; 25:4, s. 871-6
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Tidskriftsartikel (refereegranskat)abstract
- OBJECTIVE: To investigate whether a threshold exists for cardiovascular risk in type 2 diabetic patients with hypertension, the association between renal function and cardiovascular risk was examined across the entire physiological range of serum creatinine. DESIGN AND METHODS: The RENAAL and LIFE studies enrolled 1513 and 1195 patients with type 2 diabetes and hypertension, respectively. The relationship between baseline serum creatinine and the risk for a composite outcome of myocardial infarction, stroke or cardiovascular death was examined using Cox regression models. To adjust for heterogeneity between studies and treatment groups, these factors were included as strata when applicable. The analyses were conducted with adjustment for age, gender, smoking, alcohol use, blood pressure, heart rate, total and high-density lipoprotein (HDL) cholesterol, hemoglobin, albuminuria and prior cardiovascular disease. RESULTS: The hazard ratios across the baseline serum creatinine categories < 0.9 mg/dl, 0.9-1.2 mg/dl, 1.2-1.6 mg/dl, 1.6-2.8 mg/dl and >or= 2.8 mg/dl were 0.51 (95% confidence interval 0.34, 0.74), 0.74 (0.55, 1.00), 1.00 (reference), 1.24 (0.96, 1.59) and 1.67 (1.17, 2.91), respectively. Baseline serum creatinine (per mg/dl) strongly predicted the composite cardiovascular endpoint in LIFE [2.82(1.74,4.56), P < 0.001], RENAAL [1.41(1.12,1.79), P < 0.001], as well as the combined studies [1.51(1.21,1.87), P < 0.001]. CONCLUSION: A progressively higher risk for the composite cardiovascular endpoint was observed with incremental baseline serum creatinine in type 2 diabetic patients with hypertension, even within the normal range. Thus, there appears to be no serum creatinine threshold level for an increased cardiovascular risk. Baseline serum creatinine was a major independent risk factor for cardiovascular disease (www.ClinicalTrials.gov number NCT00308347).
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| 20. |
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| 21. |
- Garcia-Lopez, R., et al.
(författare)
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The GRAVITY young stellar object survey XII. The hot gas disk component in Herbig Ae/Be stars
- 2024
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Ingår i: Astronomy and Astrophysics. - 0004-6361 .- 1432-0746. ; 684
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Tidskriftsartikel (refereegranskat)abstract
- Context. The region of protoplanetary disks closest to a star (within 1–2 au) is shaped by a number of different processes, from accretion of the disk material onto the central star to ejection in the form of winds and jets. Optical and near-IR emission lines are potentially good tracers of inner disk processes if very high spatial and/or spectral resolution are achieved. Aims. In this paper, we exploit the capabilities of the VLTI-GRAVITY near-IR interferometer to determine the location and kinematics of the hydrogen emission line Brγ. Methods. We present VLTI-GRAVITY observations of the Brγ line for a sample of 26 stars of intermediate mass (HAEBE), the largest sample so far analysed with near-IR interferometry. Results. The Brγ line was detected in 17 objects. The emission is very compact (in most cases only marginally resolved), with a size of 10–30 R∗(1–5 mas). About half of the total flux comes from even smaller regions, which are unresolved in our data. For eight objects, it was possible to determine the position angle (PA) of the line-emitting region, which is generally in agreement with that of the inner-dusty disk emitting the K-band continuum. The position-velocity pattern of the Brγ line-emitting region of the sampled objects is roughly consistent with Keplerian rotation. The exception is HD 45677, which shows more extended emission and more complex kinematics. The most likely scenario for the Brγ origin is that the emission comes from an MHD wind launched very close to the central star, in a region well within the dust sublimation radius. An origin in the bound gas layer at the disk surface cannot be ruled out, while accreting matter provides only a minor fraction of the total flux. Conclusions. These results show the potential of near-IR spectro-interferometry to study line emission in young stellar objects.
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| 22. |
- Lagrange, A. M., et al.
(författare)
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Unveiling the beta Pictoris system, coupling high contrast imaging, interferometric, and radial velocity data
- 2020
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Ingår i: Astronomy and Astrophysics. - : EDP Sciences. - 0004-6361 .- 1432-0746. ; 642
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Tidskriftsartikel (refereegranskat)abstract
- Context. The nearby and young beta Pictoris system hosts a well resolved disk, a directly imaged massive giant planet orbiting at similar or equal to 9 au, as well as an inner planet orbiting at similar or equal to 2.7 au, which was recently detected through radial velocity (RV). As such, it offers several unique opportunities for detailed studies of planetary system formation and early evolution.Aims. We aim to further constrain the orbital and physical properties of beta Pictoris b and c using a combination of high contrast imaging, long base-line interferometry, and RV data. We also predict the closest approaches or the transit times of both planets, and we constrain the presence of additional planets in the system.Methods. We obtained six additional epochs of SPHERE data, six additional epochs of GRAVITY data, and five additional epochs of RV data. We combined these various types of data in a single Markov-chain Monte Carlo analysis to constrain the orbital parameters and masses of the two planets simultaneously. The analysis takes into account the gravitational influence of both planets on the star and hence their relative astrometry. Secondly, we used the RV and high contrast imaging data to derive the probabilities of presence of additional planets throughout the disk, and we tested the impact of absolute astrometry.Results. The orbital properties of both planets are constrained with a semi-major axis of 9.8 0.4 au and 2.7 +/- 0.02 au for b and c, respectively, and eccentricities of 0.09 +/- 0.1 and 0.27 +/- 0.07, assuming the HIPPARCOS distance. We note that despite these low fitting error bars, the eccentricity of beta Pictoris c might still be over-estimated. If no prior is provided on the mass of beta Pictoris b, we obtain a very low value that is inconsistent with what is derived from brightness-mass models. When we set an evolutionary model motivated prior to the mass of beta Pictoris b, we find a solution in the 10-11 M-Jup range. Conversely, beta Pictoris c's mass is well constrained, at 7.8 +/- 0.4 M-Jup, assuming both planets are on coplanar orbits. These values depend on the assumptions on the distance of the beta Pictoris system. The absolute astrometry HIPPARCOS-Gaia data are consistent with the solutions presented here at the 2 sigma level, but these solutions are fully driven by the relative astrometry plus RV data. Finally, we derive unprecedented limits on the presence of additional planets in the disk. We can now exclude the presence of planets that are more massive than about 2.5 M-Jup closer than 3 au, and more massive than 3.5 M-Jup between 3 and 7.5 au. Beyond 7.5 au, we exclude the presence of planets that are more massive than 1-2 M-Jup.Conclusions. Combining relative astrometry and RVs allows one to precisely constrain the orbital parameters of both planets and to give lower limits to potential additional planets throughout the disk. The mass of beta Pictoris c is also well constrained, while additional RV data with appropriate observing strategies are required to properly constrain the mass of beta Pictoris b.
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| 23. |
- Malachias, Marcus V. B., et al.
(författare)
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NT-proBNP by Itself Predicts Death and Cardiovascular Events in High-Risk Patients With Type 2 Diabetes Mellitus
- 2020
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Ingår i: Journal of the American Heart Association. - : Wiley-Blackwell Publishing Inc.. - 2047-9980. ; 9:19
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Tidskriftsartikel (refereegranskat)abstract
- BackgroundNT‐proBNP (N‐terminal pro‐B‐type natriuretic peptide) improves the discriminatory ability of risk‐prediction models in type 2 diabetes mellitus (T2DM) but is not yet used in clinical practice. We assessed the discriminatory strength of NT‐proBNP by itself for death and cardiovascular events in high‐risk patients with T2DM.Methods and ResultsCox proportional hazards were used to create a base model formed by 20 variables. The discriminatory ability of the base model was compared with that of NT‐proBNP alone and with NT‐proBNP added, using C‐statistics. We studied 5509 patients (with complete data) of 8561 patients with T2DM and cardiovascular and/or chronic kidney disease who were enrolled in the ALTITUDE (Aliskiren in Type 2 Diabetes Using Cardiorenal Endpoints) trial. During a median 2.6‐year follow‐up period, 469 patients died and 768 had a cardiovascular composite outcome (cardiovascular death, resuscitated cardiac arrest, nonfatal myocardial infarction, stroke, or heart failure hospitalization). NT‐proBNP alone was as discriminatory as the base model for predicting death (C‐statistic, 0.745 versus 0.744, P=0.95) and the cardiovascular composite outcome (C‐statistic, 0.723 versus 0.731, P=0.37). When NT‐proBNP was added, it increased the predictive ability of the base model for death (C‐statistic, 0.779 versus 0.744, P<0.001) and for cardiovascular composite outcome (C‐statistic, 0.763 versus 0.731, P<0.001).ConclusionsIn high‐risk patients with T2DM, NT‐proBNP by itself demonstrated discriminatory ability similar to a multivariable model in predicting both death and cardiovascular events and should be considered for risk stratification.
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| 24. |
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| 25. |
- Riemens, D. P., et al.
(författare)
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Towards Scalable Arithmetic Units with Graceful Degradation
- 2014
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Ingår i: Transactions on Embedded Computing Systems. - : Association for Computing Machinery (ACM). - 1558-3465 .- 1539-9087. ; 13:4
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Tidskriftsartikel (refereegranskat)abstract
- This article presents a new family of scalable arithmetic units (ScAUs) targeting resource-constrained, embedded devices. We, first, study the performance, power, area and scalability properties of general adders. Next, suitable error-detection schemes for low-power embedded systems are discussed. As a result, our ScAUs are enhanced with a suitable error-detection scheme, resulting in a Parity-Checked ScAU (PCScAU) design. The PCScAU strikes a flexible trade-off between space and time redundancy, offering dependability similar to high-end techniques for the area and power cost of low-end approaches. An alternative design, the Precision-Scalable Arithmetic Unit (PScAU) maintains throughput with degraded precision in case of hardware failures. The PScAU is targeting dependable applications where latency rather than numerical accuracy is more important. The PScAU's downscaled mode is also interesting for runtime thermal management due to its advantageous power consumption. We implemented and synthesized the PCScAU, PScAU and a few important reference designs (double-, triple- and quadruple-modular-redundancy adders with/without input gating) in 90-nm UMC technology. Overall, the PC-ScAU ranks first in 9 out of 10 power-delay-area (PDA)-product variants. It exhibits 16% area savings and 12% performance speedup for 7% increase in total power consumption, compared to the cheapest form of conventional hardware replication with the same fault coverage. The PDA product of the PCScAU is, thus, reduced by 21%. It is interesting that, while total power slightly increases, the PCScAU static power in fact decreases by 14%. Therefore, for newer technology nodes where the static power component is significant, the PCScAU can also achieve-next to performance and area - significant power improvements.
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| 26. |
- Smaragdos, G., et al.
(författare)
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BrainFrame: a node-level heterogeneous accelerator platform for neuron simulations
- 2017
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Ingår i: Journal of Neural Engineering. - : IOP Publishing. - 1741-2560 .- 1741-2552. ; 14:6
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Tidskriftsartikel (refereegranskat)abstract
- Objective: The advent of High-Performance Computing (HPC) in recent years has led to its increasing use in brain study through computational models. The scale and complexity of such models are constantly increasing, leading to challenging computational requirements. Even though modern HPC platforms can often deal with such challenges, the vast diversity of the modeling field does not permit for a homogeneous acceleration platform to effectively address the complete array of modeling requirements. Approach: In this paper we propose and build BrainFrame, a heterogeneous acceleration platform that incorporates three distinct acceleration technologies, an Intel Xeon-Phi CPU, a NVidia GP-GPU and a Maxeler Dataflow Engine. The PyNN software framework is also integrated into the platform. As a challenging proof of concept, we analyze the performance of BrainFrame on different experiment instances of a state-of-the-art neuron model, representing the Inferior-Olivary Nucleus using a biophysically-meaningful, extended Hodgkin-Huxley representation. The model instances take into account not only the neuronal-network dimensions but also different network-connectivity densities, which can drastically affect the workload's performance characteristics. Main results: The combined use of different HPC fabrics demonstrated that BrainFrame is better able to cope with the modeling diversity encountered in realistic experiments. Our performance analysis shows clearly that the model directly affects performance and all three technologies are required to cope with all the model use cases. Significance: The BrainFrame framework is designed to transparently configure and select the appropriate back-end accelerator technology for use per simulation run. The PyNN integration provides a familiar bridge to the vast number of models already available. Additionally, it gives a clear roadmap for extending the platform support beyond the proof of concept, with improved usability and directly useful features to the computational-neuroscience community, paving the way for wider adoption.
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| 27. |
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| 28. |
- Vuoksimaa, E, et al.
(författare)
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Aggression and academic performance
- 2017
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Ingår i: BEHAVIOR GENETICS. - 0001-8244. ; 47:6, s. 656-656
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Konferensbidrag (övrigt vetenskapligt/konstnärligt)
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| 29. |
- Vuoksimaa, E., et al.
(författare)
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Higher aggression is related to poorer academic performance in compulsory education
- 2021
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Ingår i: Journal of Child Psychology and Psychiatry. - : Wiley. - 0021-9630 .- 1469-7610. ; 62:3, s. 327-338
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Tidskriftsartikel (refereegranskat)abstract
- Background To conduct a comprehensive assessment of the association between aggression and academic performance in compulsory education. Method We studied aggression and academic performance in over 27,000 individuals from four European twin cohorts participating in the ACTION consortium (Aggression in Children: Unraveling gene-environment interplay to inform Treatment and InterventiON strategies). Individual level data on aggression at ages 7-16 were assessed by three instruments (Achenbach System of Empirically Based Assessment, Multidimensional Peer Nomination Inventory, Strengths and Difficulties Questionnaire) including parental, teacher and self-reports. Academic performance was measured with teacher-rated grade point averages (ages 12-14) or standardized test scores (ages 12-16). Random effect meta-analytical correlations with academic performance were estimated for parental ratings (in all four cohorts) and self-ratings (in three cohorts). Results All between-family analyses indicated significant negative aggression-academic performance associations with correlations ranging from -.06 to -.33. Results were similar across different ages, instruments and raters and either with teacher-rated grade point averages or standardized test scores as measures of academic performance. Meta-analytical r's were -.20 and -.23 for parental and self-ratings, respectively. In within-family analyses of all twin pairs, the negative aggression-academic performance associations were statistically significant in 14 out of 17 analyses (r = -.17 for parental- and r = -.16 for self-ratings). Separate analyses in monozygotic (r = -.07 for parental and self-ratings), same-sex dizygotic (r's = -.16 and -.17 for parental and self-ratings) and opposite-sex dizygotic (r's = -.21 and -.19 for parental and self-ratings) twin pairs suggested partial confounding by genetic effects. Conclusions There is a robust negative association between aggression and academic performance in compulsory education. Part of these associations were explained by shared genetic effects, but some evidence of a negative association between aggression and academic performance remained even in within-family analyses of monozygotic twin pairs.
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