SwePub
Sök i SwePub databas

  Utökad sökning

Träfflista för sökning "WFRF:(Simpson Richard J.) srt2:(2015-2019)"

Sökning: WFRF:(Simpson Richard J.) > (2015-2019)

  • Resultat 1-16 av 16
Sortera/gruppera träfflistan
   
NumreringReferensOmslagsbildHitta
1.
  •  
2.
  •  
3.
  •  
4.
  • Joffrin, E., et al. (författare)
  • Overview of the JET preparation for deuterium-tritium operation with the ITER like-wall
  • 2019
  • Ingår i: Nuclear Fusion. - : IOP Publishing. - 1741-4326 .- 0029-5515. ; 59:11
  • Forskningsöversikt (refereegranskat)abstract
    • For the past several years, the JET scientific programme (Pamela et al 2007 Fusion Eng. Des. 82 590) has been engaged in a multi-campaign effort, including experiments in D, H and T, leading up to 2020 and the first experiments with 50%/50% D-T mixtures since 1997 and the first ever D-T plasmas with the ITER mix of plasma-facing component materials. For this purpose, a concerted physics and technology programme was launched with a view to prepare the D-T campaign (DTE2). This paper addresses the key elements developed by the JET programme directly contributing to the D-T preparation. This intense preparation includes the review of the physics basis for the D-T operational scenarios, including the fusion power predictions through first principle and integrated modelling, and the impact of isotopes in the operation and physics of D-T plasmas (thermal and particle transport, high confinement mode (H-mode) access, Be and W erosion, fuel recovery, etc). This effort also requires improving several aspects of plasma operation for DTE2, such as real time control schemes, heat load control, disruption avoidance and a mitigation system (including the installation of a new shattered pellet injector), novel ion cyclotron resonance heating schemes (such as the three-ions scheme), new diagnostics (neutron camera and spectrometer, active Alfven eigenmode antennas, neutral gauges, radiation hard imaging systems...) and the calibration of the JET neutron diagnostics at 14 MeV for accurate fusion power measurement. The active preparation of JET for the 2020 D-T campaign provides an incomparable source of information and a basis for the future D-T operation of ITER, and it is also foreseen that a large number of key physics issues will be addressed in support of burning plasmas.
  •  
5.
  • Pennells, Lisa, et al. (författare)
  • Equalization of four cardiovascular risk algorithms after systematic recalibration : individual-participant meta-analysis of 86 prospective studies
  • 2019
  • Ingår i: European Heart Journal. - : Oxford University Press (OUP). - 0195-668X .- 1522-9645. ; 40:7, s. 621-
  • Tidskriftsartikel (refereegranskat)abstract
    • Aims: There is debate about the optimum algorithm for cardiovascular disease (CVD) risk estimation. We conducted head-to-head comparisons of four algorithms recommended by primary prevention guidelines, before and after ‘recalibration’, a method that adapts risk algorithms to take account of differences in the risk characteristics of the populations being studied.Methods and results: Using individual-participant data on 360 737 participants without CVD at baseline in 86 prospective studies from 22 countries, we compared the Framingham risk score (FRS), Systematic COronary Risk Evaluation (SCORE), pooled cohort equations (PCE), and Reynolds risk score (RRS). We calculated measures of risk discrimination and calibration, and modelled clinical implications of initiating statin therapy in people judged to be at ‘high’ 10 year CVD risk. Original risk algorithms were recalibrated using the risk factor profile and CVD incidence of target populations. The four algorithms had similar risk discrimination. Before recalibration, FRS, SCORE, and PCE over-predicted CVD risk on average by 10%, 52%, and 41%, respectively, whereas RRS under-predicted by 10%. Original versions of algorithms classified 29–39% of individuals aged ≥40 years as high risk. By contrast, recalibration reduced this proportion to 22–24% for every algorithm. We estimated that to prevent one CVD event, it would be necessary to initiate statin therapy in 44–51 such individuals using original algorithms, in contrast to 37–39 individuals with recalibrated algorithms.Conclusion: Before recalibration, the clinical performance of four widely used CVD risk algorithms varied substantially. By contrast, simple recalibration nearly equalized their performance and improved modelled targeting of preventive action to clinical need.
  •  
6.
  • Sanchez-Gonzalez, A., et al. (författare)
  • Accurate prediction of X-ray pulse properties from a free-electron laser using machine learning
  • 2017
  • Ingår i: Nature Communications. - : Springer Science and Business Media LLC. - 2041-1723. ; 8
  • Tidskriftsartikel (refereegranskat)abstract
    • Free-electron lasers providing ultra-short high-brightness pulses of X-ray radiation have great potential for a wide impact on science, and are a critical element for unravelling the structural dynamics of matter. To fully harness this potential, we must accurately know the X-ray properties: intensity, spectrum and temporal profile. Owing to the inherent fluctuations in free-electron lasers, this mandates a full characterization of the properties for each and every pulse. While diagnostics of these properties exist, they are often invasive and many cannot operate at a high-repetition rate. Here, we present a technique for circumventing this limitation. Employing a machine learning strategy, we can accurately predict X-ray properties for every shot using only parameters that are easily recorded at high-repetition rate, by training a model on a small set of fully diagnosed pulses. This opens the door to fully realizing the promise of next-generation high-repetition rate X-ray lasers.
  •  
7.
  • Sanchez-Gonzalez, A., et al. (författare)
  • Auger electron and photoabsorption spectra of glycine in the vicinity of the oxygen K-edge measured with an X-FEL
  • 2015
  • Ingår i: Journal of Physics B-Atomic Molecular and Optical Physics. - : IOP Publishing. - 0953-4075 .- 1361-6455. ; 48:23
  • Tidskriftsartikel (refereegranskat)abstract
    • We report the first measurement of the near oxygen K-edge auger spectrum of the glycine molecule. Our work employed an x-ray free electron laser as the photon source operated with input photon energies tunable between 527 and 547 eV. Complete electron spectra were recorded at each photon energy in the tuning range, revealing resonant and non-resonant auger structures. Finally ab initio theoretical predictions are compared with the measured above the edge auger spectrum and an assignment of auger decay channels is performed.
  •  
8.
  • Middeldorp, Christel M., et al. (författare)
  • The Early Growth Genetics (EGG) and EArly Genetics and Lifecourse Epidemiology (EAGLE) consortia : design, results and future prospects
  • 2019
  • Ingår i: European Journal of Epidemiology. - : Springer Science and Business Media LLC. - 0393-2990 .- 1573-7284. ; 34:3, s. 279-300
  • Tidskriftsartikel (refereegranskat)abstract
    • The impact of many unfavorable childhood traits or diseases, such as low birth weight and mental disorders, is not limited to childhood and adolescence, as they are also associated with poor outcomes in adulthood, such as cardiovascular disease. Insight into the genetic etiology of childhood and adolescent traits and disorders may therefore provide new perspectives, not only on how to improve wellbeing during childhood, but also how to prevent later adverse outcomes. To achieve the sample sizes required for genetic research, the Early Growth Genetics (EGG) and EArly Genetics and Lifecourse Epidemiology (EAGLE) consortia were established. The majority of the participating cohorts are longitudinal population-based samples, but other cohorts with data on early childhood phenotypes are also involved. Cohorts often have a broad focus and collect(ed) data on various somatic and psychiatric traits as well as environmental factors. Genetic variants have been successfully identified for multiple traits, for example, birth weight, atopic dermatitis, childhood BMI, allergic sensitization, and pubertal growth. Furthermore, the results have shown that genetic factors also partly underlie the association with adult traits. As sample sizes are still increasing, it is expected that future analyses will identify additional variants. This, in combination with the development of innovative statistical methods, will provide detailed insight on the mechanisms underlying the transition from childhood to adult disorders. Both consortia welcome new collaborations. Policies and contact details are available from the corresponding authors of this manuscript and/or the consortium websites.
  •  
9.
  • Dahal, Prabin, et al. (författare)
  • Competing risk events in antimalarial drug trials in uncomplicated Plasmodium falciparum malaria : a WorldWide Antimalarial Resistance Network individual participant data meta-analysis
  • 2019
  • Ingår i: Malaria Journal. - : BMC. - 1475-2875. ; 18
  • Tidskriftsartikel (refereegranskat)abstract
    • Background: Therapeutic efficacy studies in uncomplicated Plasmodium falciparum malaria are confounded by new infections, which constitute competing risk events since they can potentially preclude/pre-empt the detection of subsequent recrudescence of persistent, sub-microscopic primary infections.Methods: Antimalarial studies typically report the risk of recrudescence derived using the Kaplan-Meier (K-M) method, which considers new infections acquired during the follow-up period as censored. Cumulative Incidence Function (CIF) provides an alternative approach for handling new infections, which accounts for them as a competing risk event. The complement of the estimate derived using the K-M method (1 minus K-M), and the CIF were used to derive the risk of recrudescence at the end of the follow-up period using data from studies collated in the WorldWide Antimalarial Resistance Network data repository. Absolute differences in the failure estimates derived using these two methods were quantified. In comparative studies, the equality of two K-M curves was assessed using the log-rank test, and the equality of CIFs using Gray's k-sample test (both at 5% level of significance). Two different regression modelling strategies for recrudescence were considered: cause-specific Cox model and Fine and Gray's sub-distributional hazard model.Results: Data were available from 92 studies (233 treatment arms, 31,379 patients) conducted between 1996 and 2014. At the end of follow-up, the median absolute overestimation in the estimated risk of cumulative recrudescence by using 1 minus K-M approach was 0.04% (interquartile range (IQR): 0.00-0.27%, Range: 0.00-3.60%). The overestimation was correlated positively with the proportion of patients with recrudescence [Pearson's correlation coefficient (rho): 0.38, 95% Confidence Interval (CI) 0.30-0.46] or new infection [rho: 0.43; 95% CI 0.35-0.54]. In three study arms, the point estimates of failure were greater than 10% (the WHO threshold for withdrawing antimalarials) when the K-M method was used, but remained below 10% when using the CIF approach, but the 95% confidence interval included this threshold.Conclusions: The 1 minus K-M method resulted in a marginal overestimation of recrudescence that became increasingly pronounced as antimalarial efficacy declined, particularly when the observed proportion of new infection was high. The CIF approach provides an alternative approach for derivation of failure estimates in antimalarial trials, particularly in high transmission settings.
  •  
10.
  • Dand, Nick, et al. (författare)
  • Exome-wide association study reveals novel psoriasis susceptibility locus at TNFSF15 and rare protective alleles in genes contributing to type I IFN signalling
  • 2017
  • Ingår i: Human Molecular Genetics. - : OXFORD UNIV PRESS. - 0964-6906 .- 1460-2083. ; 26:21, s. 4301-4313
  • Tidskriftsartikel (refereegranskat)abstract
    • Psoriasis is a common inflammatory skin disorder for which multiple genetic susceptibility loci have been identified, but few resolved to specific functional variants. In this study, we sought to identify common and rare psoriasis-associated gene-centric variation. Using exome arrays we genotyped four independent cohorts, totalling 11 861 psoriasis cases and 28 610 controls, aggregating the dataset through statistical meta-analysis. Single variant analysis detected a previously unreported risk locus at TNFSF15 (rs6478108; P = 1.50 x 10(-8), OR = 1.10), and association of common protein-altering variants at 11 loci previously implicated in psoriasis susceptibility. We validate previous reports of protective low-frequency protein-altering variants within IFIH1 (encoding an innate antiviral receptor) and TYK2 (encoding a Janus kinase), in each case establishing a further series of protective rare variants (minor allele frequency amp;lt; 0.01) via gene-wide aggregation testing (IFIH1: p(burden) = 2.53 x 10(-7), OR = 0.707; TYK2: p(burden) = 6.17 x 10(-4), OR = 0.744). Both genes play significant roles in type I interferon (IFN) production and signalling. Several of the protective rare and low-frequency variants in IFIH1 and TYK2 disrupt conserved protein domains, highlighting potential mechanisms through which their effect may be exerted.
  •  
11.
  • Alahmadi, Fahad, et al. (författare)
  • Measures of adherence in patients with severe asthma prescribed systemic steroids in the U-BIOPRED cohort
  • 2018
  • Ingår i: European Respiratory Journal. - : European Respiratory Society. - 0903-1936 .- 1399-3003. ; 52
  • Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)abstract
    • Introduction: Rates of sub-optimal adherence to medications in asthma range up to 70%; the impact in severe asthma is likely to be particularly high. We measured self-reported adherence in participants in the U-BIOPRED cohort prescribed daily prednisolone using the Medication Adherence Response Scale (MARS), and compared to measured urinary prednisolone and metabolites in order to determine: 1. the prevalence of suboptimal adherence by each method; 2. the ability of MARS to predict urinary steroid detection.Methods: Participants completed the MARS, and/or provided urine samples (analysed for prednisolone and metabolites by LCMS). The performance characteristics of the MARS predicting undetected urinary steroid were calculated in the subgroup having both tests.Results: 181 participants currently taking regular oral corticosteroids were included, 59% female, mean (SD) age 54(12)yrs, FEV1 64.7(20.4)% predicted. Sub-optimal adherence (MARS score < 4.5) was reported in 62 participants, and 76 did not have detectable urinary prednisolone or metabolites. Good adherence by both methods was detected in only 52 participants (34%, see table). There was no difference in daily prednisolone dose between detectable and undetectable metabolites groups (p=0.848).Conclusion: Low levels of adherence to treatment in severe asthma is a common problem, when measured either directly or self-reported. There was very poor agreement (48% concordance) between these two methods, and we suggest that, for now both approaches should be used.
  •  
12.
  • Kim, Dae-Kyum, et al. (författare)
  • EVpedia: A Community Web Portal for Extracellular Vesicles Research
  • 2015
  • Ingår i: Bioinformatics. - : Oxford University Press (OUP). - 1367-4803 .- 1367-4811. ; 31:6, s. 933-939
  • Tidskriftsartikel (refereegranskat)abstract
    • Motivation: Extracellular vesicles (EVs) are spherical bilayered proteolipids, harboring various bioactive molecules. Due to the complexity of the vesicular nomenclatures and components, online searches for EV-related publications and vesicular components are currently challenging. Results: We present an improved version of EVpedia, a public database for EVs research. This community web portal contains a database of publications and vesicular components, identification of orthologous vesicular components, bioinformatic tools and a personalized function. EVpedia includes 6879 publications, 172 080 vesicular components from 263 high-throughput datasets, and has been accessed more than 65 000 times from more than 750 cities. In addition, about 350 members from 73 international research groups have participated in developing EVpedia. This free web-based database might serve as a useful resource to stimulate the emerging field of EV research.
  •  
13.
  • Bosman, Sarah E. I., et al. (författare)
  • A deep search for metals near redshift 7 : the line of sight towards ULAS J1120+0641
  • 2017
  • Ingår i: Monthly notices of the Royal Astronomical Society. - : Oxford University Press (OUP). - 0035-8711 .- 1365-2966. ; 470:2, s. 1919-1934
  • Tidskriftsartikel (refereegranskat)abstract
    • We present a search for metal absorption line systems at the highest redshifts to date using a deep (30 h) Very Large Telescope/X=Shooter spectrum of the z = 7.084 quasi-stellar object (QSO) ULAS J1120+0641. We detect seven intervening systems at z > 5.5, with the highest redshift system being a C IV absorber at z = 6.51. We find tentative evidence that the mass density of C IV remains flat or declines with redshift at z < 6, while the number density of C II systems remains relatively flat over 5 < z < 7. These trends are broadly consistent with models of chemical enrichment by star formation-driven winds that include a softening of the ultraviolet background towards higher redshifts. We find a larger number of weak (W-rest < 0.3 angstrom) Mg II systems over 5.9 < z < 7.0 than predicted by a power-law fit to the number density of stronger systems. This is consistent with trends in the number density of weak Mg II systems at z less than or similar to 2.5, and suggests that the mechanisms that create these absorbers are already in place at z similar to 7. Finally, we investigate the associated narrow Si IV, C IV and N V absorbers located near the QSO redshift, and find that at least one component shows evidence of partial covering of the continuum source.
  •  
14.
  •  
15.
  • Venemans, Bram P., et al. (författare)
  • The Compact, similar to 1 kpc Host Galaxy of a Quasar at a Redshift of 7.1
  • 2017
  • Ingår i: Astrophysical Journal. - : American Astronomical Society. - 0004-637X .- 1538-4357. ; 837:2
  • Tidskriftsartikel (refereegranskat)abstract
    • We present Atacama Large Millimeter/submillimeter Array (ALMA) observations of the [C II] fine-structure line and the underlying far-infrared (FIR) dust continuum emission in J1120+0641, the most distant quasar currently known (z = 7.1). We also present observations targeting the CO(2-1), CO(7-6), and [C I] 369 mu m lines in the same source obtained at the Very Large Array and Plateau de Bure Interferometer. We find a [C II] line flux of F-[C II] = 1.11 +/- 0.10 Jy km s(-1) and a continuum flux density of S-227 GHz = 0.53 +/- 0.04 mJy beam(-1), consistent with previous unresolved measurements. No other source is detected in continuum or [C II] emission in the field covered by ALMA (similar to 25 ''). At the resolution of our ALMA observations (0.'' 23, or 1.2 kpc, a factor of similar to 70 smaller beam area compared to previous measurements), we find that the majority of the emission is very compact: a high fraction (similar to 80%) of the total line and continuum flux is associated with a region 1-1.5 kpc in diameter. The remaining similar to 20% of the emission is distributed over a larger area with radius. 4 kpc. The [C II] emission does not exhibit ordered motion on kiloparsec scales: applying the virial theorem yields an upper limit on the dynamical mass of the host galaxy of (4.3 +/- 0.9) x 10(10) M-circle dot, only similar to 20 x higher than the central black hole (BH). The other targeted lines (CO(2-1), CO(7-6), and [C I]) are not detected, but the limits of the line ratios with respect to the [C II] emission imply that the heating in the quasar host is dominated by star formation, and not by the accreting BH. The star formation rate (SFR) implied by the FIR continuum is 105-340 M-circle dot yr(-1), with a resulting SFR surface density of similar to 100-350 M yr(-1) kpc(-2), well below the value for Eddington-accretion-limited star formation.
  •  
16.
  • Woolway, R. Iestyn, et al. (författare)
  • Diel Surface Temperature Range Scales with Lake Size
  • 2016
  • Ingår i: PLOS ONE. - : Public Library of Science (PLoS). - 1932-6203. ; 11:3
  • Tidskriftsartikel (refereegranskat)abstract
    • Ecological and biogeochemical processes in lakes are strongly dependent upon water temperature. Long-term surface warming of many lakes is unequivocal, but little is known about the comparative magnitude of temperature variation at diel timescales, due to a lack of appropriately resolved data. Here we quantify the pattern and magnitude of diel temperature variability of surface waters using high-frequency data from 100 lakes. We show that the near-surface diel temperature range can be substantial in summer relative to long-term change and, for lakes smaller than 3 km(2), increases sharply and predictably with decreasing lake area. Most small lakes included in this study experience average summer diel ranges in their near-surface temperatures of between 4 and 7 degrees C. Large diel temperature fluctuations in the majority of lakes undoubtedly influence their structure, function and role in biogeochemical cycles, but the full implications remain largely unexplored.
  •  
Skapa referenser, mejla, bekava och länka
  • Resultat 1-16 av 16

Kungliga biblioteket hanterar dina personuppgifter i enlighet med EU:s dataskyddsförordning (2018), GDPR. Läs mer om hur det funkar här.
Så här hanterar KB dina uppgifter vid användning av denna tjänst.

 
pil uppåt Stäng

Kopiera och spara länken för att återkomma till aktuell vy