Medical imaging has enormous potential for early disease prediction, but is impeded by the difficulty and expense of acquiring datasets prior to symptom onset. UK Biobank aims to address this problem directly by acquiring high quality, consistently acquired imaging data from 100,000 predominantly healthy participants, with health outcomes tracked over coming decades. The brain imaging includes structural, diffusion and functional modalities. Along with body and cardiac imaging, genetics, lifestyle measures, biological phenotyping and health records, this is expected to enable discovery of imaging markers of a broad range of diseases at their earliest stages, as well Users may view, print, copy, and download text and data-mine the content in such documents, for the purposes of academic research, subject always to the full Conditions of use
BackgroundUK Biobank’s ambitious aim is to perform cardiovascular magnetic resonance (CMR) in 100,000 people previously recruited into this prospective cohort study of half a million 40-69 year-olds.Methods/designWe describe the CMR protocol applied in UK Biobank’s pilot phase, which will be extended into the main phase with three centres using the same equipment and protocols. The CMR protocol includes white blood CMR (sagittal anatomy, coronary and transverse anatomy), cine CMR (long axis cines, short axis cines of the ventricles, coronal LVOT cine), strain CMR (tagging), flow CMR (aortic valve flow) and parametric CMR (native T1 map).DiscussionThis report will serve as a reference to researchers intending to use the UK Biobank resource or to replicate the UK Biobank cardiovascular magnetic resonance protocol in different settings.
Three experiments investigated the role of working memory in various aspects of thinking in chess. Experiment 1 examined the immediate memory for brieflypresented chess positions from master games in players from a wide range of abilities, following the imposition of various secondary tasks designed to block separate components of working memory. Suppression of the articulatory loop (by preventing subvocal rehearsal) had no effect on measures of recall, whereas blocking the visuospatial sketchpad (by manipulation of a keypad) and blocking the central executive (by random letter generation) had equivalent disruptive effects, in comparison with a control condition. Experiment 2 investigated the effects of similar secondary tasks on the solution (i.e., move selection) of tactical chess positions, and a similar pattern was found, except that blocking the central executive was much more disruptive than in Experiment 1. Experiment 3 compared performance on two types of primary task, one concerned with solving chess positions as in Experiment 2, and the other a sentence-rearrangement task. The secondary tasks in each case were both designed to block the central executive, but one was verbal (vocal generation of random numbers), while the other was spatial in nature (random generation of keypresses). Performance ofthe spatial secondary task was affected to a greater extent by the chess primary task than by the verbal primary task, whereas there were no differential effects on these secondary tasks by the verbal primary task. In none of the three experiments were there any differential effects between weak and strong players. These results are interpreted in the context of the workingmemory model and previous theories of the nature of cognition in chess.Thinking in chess is of particular interest to the psychologist, in that it can be represented both visuospatially-as a sequence of moves on a chessboard-and propositionally--either according to various types of notation or as verbal protocols, such as those collected by early researchers (e.g., de Groot, 1965). Variation in these modes of representation could conceivably distinguish strong from weak players, and even underlie these individual differences in chess skill. Milojkovic (1982) has proposed that stronger players rely to a greater extent on propositional coding, supporting the claim with a demonstration that the time taken by a master to decide whether a particular piece was under attack is independent of the physical details of the problem, such as the spatial separation of the pieces, whereas the latencies ofa group of weaker players were affected by such spatial features.Holding (1985) has criticized the emphasis on spatial processing by pointing out the verbal components of chess and referring to evidence that top players have been reported to exhibit superior verbal skills, as manifested particularly by their competence in acquiring foreign languages and their prevalence in professional writing occupations.We thank Pertii Saariluoma for helpful discussions...
We estimated right ventricular volume and ejection by two-dimensional echocardiography (2DE) and compared the measurements with those obtained by right ventricular cineangiography (ANGIO) in 20 children whose ages ranged from 1 month to 10 years and who had a variety of congenital defects. The two echocardiographic planes used for calculating volume were the apical four-chamber (A4C) and parasternal short-axis (SA) planes. End diastolic volume (EDV) and end systolic volume (ESV) were calculated from these planes by single-plane area-length methods. The EDV and ESV were uniformly underestimated, but the estimate of ejection fraction (EF) was satisfactory. For EF, r = 0.83 from the apical four-chamber view and r = 0.78 from the short-axis view. The axes of the two echocardiographic planes passed through different segments of the right ventricle (RV) and we found that the value given by adding the volumes obtained from the two single-plane segments correlated quite well with the value obtained by angiography: for EDV, 2DE = 0.62 ANGIO + 7.0, r = 0.81, standard error of the estimate (s.e.e.) = 15.4 ml; for ESV, 2DE = 0.82 ANGIO + 1.4, r = 0.85, s.e.e. = 6.5 ml; and for EF, 2DE = 0.66 ANGIO + 17.8, r = 0.82, s.e.e. = 7.4 ml. Two-dimensional echocardiography can be used to evaluate right ventricular EF derived from volume measurements or from each of the echocardiographic planes of which, in our series, the apical four-chamber EF provided the better correlation.
Objectives This study aimed to develop an inexpensive, readily available prognostic indicator in acute decompensated heart failure patients to guide management and improve outcome. Prognostic biomarkers for heart failure exist but are expensive and not routinely performed. Increasing plasma volume has been associated with worse outcomes. Setting UK University Teaching Hospital. Design Observational Cohort study. Participants 967 patients with acute decompensated heart failure. Methods Haemoglobin and haematocrit were measured at admission and discharge and were used to calculate the plasma volume change using the Strauss-Davis-Rosenbaum formula. Main outcome measures Endpoints were death and the composite of death and/or heart failure hospitalisation. Change in plasma volume was added to ADHERE scoring to determine predictive value. Results During follow-up, 536 died and 626 died or were hospitalised with heart failure. Multivariable Cox models showed change in plasma volume was an independent predictor of mortality (hazard ratio (HR) [95% confidence interval (CI)]: 1.150 [1.031–1.283], p = 0.012) and death or heart failure hospitalisation (HR: 1.138 [1.029–1.259], p = 0.012). Kaplan–Meier analysis of change in plasma volume tertiles for outcome measures showed significant difference for the top tertile compared to the lower two. Multivariable analysis of change in plasma volume with ADHERE scoring showed change in plasma volume change remained an independent predictor of death (HR: 1.138 [1.026–1.261], p = 0.015) and death or heart failure hospitalisation (HR: 1.129 [1.025–1.243], p = 0.014). Conclusions Change in plasma volume over an admission can be used for prognostication and adds value to the ADHERE score. Change in plasma volume can be easily and inexpensively calculated from routine blood tests. Clinically, this may facilitate targeted treatment of acute decompensated heart failure patients at greatest risk.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
customersupport@researchsolutions.com
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
This site is protected by reCAPTCHA and the Google Privacy Policy and Terms of Service apply.
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.